diff --git a/export/index.template.html b/export/index.template.html
index e9d2324..bacad1a 100644
--- a/export/index.template.html
+++ b/export/index.template.html
@@ -75,6 +75,96 @@
       .hidden {
         display: none;
       }
+      #passphrase-form-div {
+        text-align: center;
+        max-width: 500px;
+        margin: 2em auto;
+        padding: 1.5em;
+        border: 1px solid #ddd;
+        border-radius: 8px;
+        background-color: #fafafa;
+      }
+      #passphrase-form-div h2 {
+        margin-top: 0;
+        color: #333;
+      }
+      #passphrase-form-div p {
+        color: #555;
+        font-size: 0.9em;
+        margin-bottom: 1.5em;
+      }
+      #passphrase-form-div label {
+        display: block;
+        text-align: left;
+        margin: 0.5em 0 0.25em 0;
+        font-weight: bold;
+        color: #444;
+      }
+      #passphrase-form-div input[type="password"] {
+        width: 100%;
+        padding: 0.6em;
+        font-size: 1em;
+        border: 1px solid #ccc;
+        border-radius: 4px;
+        box-sizing: border-box;
+        margin-bottom: 0.5em;
+      }
+      #passphrase-form-div input[type="password"]:focus {
+        outline: none;
+        border-color: #666;
+      }
+      #encrypt-and-export {
+        color: white;
+        width: 100%;
+        font-size: 1em;
+        padding: 0.75em;
+        margin-top: 1em;
+        border-radius: 4px;
+        background-color: rgb(50, 44, 44);
+        border: 1px rgb(33, 33, 33) solid;
+        cursor: pointer;
+      }
+      #encrypt-and-export:hover {
+        background-color: rgb(70, 64, 64);
+      }
+      #passphrase-error {
+        color: #c0392b;
+        font-size: 0.9em;
+        margin: 0.5em 0;
+        text-align: left;
+      }
+      #passphrase-strength {
+        margin-top: 0.5em;
+        text-align: left;
+      }
+      #passphrase-strength-bar {
+        height: 6px;
+        border-radius: 3px;
+        background-color: #e0e0e0;
+        overflow: hidden;
+        margin-bottom: 0.3em;
+      }
+      #passphrase-strength-fill {
+        height: 100%;
+        width: 0%;
+        transition: width 0.3s ease, background-color 0.3s ease;
+      }
+      #passphrase-strength-text {
+        font-size: 0.8em;
+        color: #666;
+      }
+      .strength-weak {
+        background-color: #e74c3c;
+      }
+      .strength-fair {
+        background-color: #f39c12;
+      }
+      .strength-good {
+        background-color: #3498db;
+      }
+      .strength-strong {
+        background-color: #27ae60;
+      }
     </style>
   </head>
 
@@ -1191,6 +1281,104 @@ <h2>Message log</h2>
           return JSON.stringify(validSettings);
         }
 
+        /**
+         * Encrypts a Uint8Array using PBKDF2 key derivation and AES-GCM-256 encryption.
+         * @param {Uint8Array} buf - The data to encrypt
+         * @param {string} passphrase - The passphrase to derive the key from
+         * @returns {Promise<Uint8Array>} - Concatenated salt || iv || ciphertext
+         */
+        async function encryptWithPassphrase(buf, passphrase) {
+          // Generate random 16-byte salt and 12-byte IV
+          const salt = crypto.getRandomValues(new Uint8Array(16));
+          const iv = crypto.getRandomValues(new Uint8Array(12));
+
+          // Import passphrase as PBKDF2 key material
+          const keyMaterial = await crypto.subtle.importKey(
+            "raw",
+            new TextEncoder().encode(passphrase),
+            "PBKDF2",
+            false,
+            ["deriveBits", "deriveKey"]
+          );
+
+          // Derive AES-256 key using PBKDF2 (600,000 iterations, SHA-256).
+          // NOTE: The iteration count must match during decryption; changing it
+          // affects compatibility with data encrypted using a different value.
+          const aesKey = await crypto.subtle.deriveKey(
+            {
+              name: "PBKDF2",
+              salt: salt,
+              iterations: 600000,
+              hash: "SHA-256",
+            },
+            keyMaterial,
+            { name: "AES-GCM", length: 256 },
+            false,
+            ["encrypt"]
+          );
+
+          // Encrypt using AES-GCM
+          const ciphertext = await crypto.subtle.encrypt(
+            { name: "AES-GCM", iv: iv },
+            aesKey,
+            buf
+          );
+
+          // Return concatenated salt || iv || ciphertext
+          const result = new Uint8Array(
+            salt.length + iv.length + ciphertext.byteLength
+          );
+          result.set(salt, 0);
+          result.set(iv, salt.length);
+          result.set(new Uint8Array(ciphertext), salt.length + iv.length);
+          return result;
+        }
+
+        /**
+         * Decrypts a buffer encrypted by encryptWithPassphrase.
+         * @param {Uint8Array} encryptedBuf - The encrypted data (salt || iv || ciphertext)
+         * @param {string} passphrase - The passphrase to derive the key from
+         * @returns {Promise<Uint8Array>} - The decrypted data
+         */
+        async function decryptWithPassphrase(encryptedBuf, passphrase) {
+          // Extract salt (bytes 0-16), iv (bytes 16-28), ciphertext (bytes 28+)
+          const salt = encryptedBuf.slice(0, 16);
+          const iv = encryptedBuf.slice(16, 28);
+          const ciphertext = encryptedBuf.slice(28);
+
+          // Import passphrase as PBKDF2 key material
+          const keyMaterial = await crypto.subtle.importKey(
+            "raw",
+            new TextEncoder().encode(passphrase),
+            "PBKDF2",
+            false,
+            ["deriveBits", "deriveKey"]
+          );
+
+          // Derive same AES key using PBKDF2
+          const aesKey = await crypto.subtle.deriveKey(
+            {
+              name: "PBKDF2",
+              salt: salt,
+              iterations: 600000,
+              hash: "SHA-256",
+            },
+            keyMaterial,
+            { name: "AES-GCM", length: 256 },
+            false,
+            ["decrypt"]
+          );
+
+          // Decrypt using AES-GCM
+          const decrypted = await crypto.subtle.decrypt(
+            { name: "AES-GCM", iv: iv },
+            aesKey,
+            ciphertext
+          );
+
+          return new Uint8Array(decrypted);
+        }
+
         return {
           initEmbeddedKey,
           generateTargetKey,
@@ -1221,6 +1409,8 @@ <h2>Message log</h2>
           validateStyles,
           getSettings,
           setSettings,
+          encryptWithPassphrase,
+          decryptWithPassphrase,
         };
       })();
     </script>
@@ -1312,6 +1502,23 @@ <h2>Message log</h2>
             TKHQ.sendMessageUp("ERROR", e.toString(), event.data["requestId"]);
           }
         }
+        if (
+          event.data &&
+          event.data["type"] == "INJECT_WALLET_EXPORT_BUNDLE_ENCRYPTED"
+        ) {
+          TKHQ.logMessage(
+            `⬇️ Received message ${event.data["type"]}:  ${event.data["value"]}, ${event.data["organizationId"]}`
+          );
+          try {
+            await onInjectWalletBundleEncrypted(
+              event.data["value"],
+              event.data["organizationId"],
+              event.data["requestId"]
+            );
+          } catch (e) {
+            TKHQ.sendMessageUp("ERROR", e.toString(), event.data["requestId"]);
+          }
+        }
         if (event.data && event.data["type"] == "APPLY_SETTINGS") {
           try {
             await onApplySettings(event.data["value"], event.data["requestId"]);
@@ -1432,6 +1639,277 @@ <h2>Message log</h2>
         TKHQ.applySettings(TKHQ.getSettings());
       }
 
+      /**
+       * Display a passphrase form to encrypt the mnemonic before exporting.
+       * @param {string} mnemonic - The wallet mnemonic to encrypt
+       * @param {string} requestId - The request ID for message correlation
+       */
+      function displayPassphraseForm(mnemonic, requestId) {
+        // Hide all existing DOM elements except scripts
+        Array.from(document.body.children).forEach((child) => {
+          if (child.tagName !== "SCRIPT") {
+            child.style.display = "none";
+          }
+        });
+
+        // Create the passphrase form container
+        const formDiv = document.createElement("form");
+        formDiv.id = "passphrase-form-div";
+
+        // Create heading
+        const heading = document.createElement("h2");
+        heading.innerText = "Encrypt Your Wallet Export";
+        formDiv.appendChild(heading);
+
+        // Create description
+        const description = document.createElement("p");
+        description.innerText =
+          "Enter a passphrase to encrypt your wallet mnemonic. You will need this passphrase to decrypt your wallet later.";
+        formDiv.appendChild(description);
+
+        // Create passphrase input
+        const passphraseLabel = document.createElement("label");
+        passphraseLabel.setAttribute("for", "export-passphrase");
+        passphraseLabel.innerText = "Passphrase";
+        formDiv.appendChild(passphraseLabel);
+
+        const passphraseInput = document.createElement("input");
+        passphraseInput.type = "password";
+        passphraseInput.id = "export-passphrase";
+        passphraseInput.placeholder = "Enter passphrase (min 8 characters)";
+        passphraseInput.required = true;
+        passphraseInput.setAttribute("aria-required", "true");
+        passphraseInput.setAttribute("autocomplete", "new-password");
+        passphraseInput.minLength = 8;
+        formDiv.appendChild(passphraseInput);
+
+        // Create passphrase strength indicator
+        const strengthDiv = document.createElement("div");
+        strengthDiv.id = "passphrase-strength";
+
+        const strengthBar = document.createElement("div");
+        strengthBar.id = "passphrase-strength-bar";
+
+        const strengthFill = document.createElement("div");
+        strengthFill.id = "passphrase-strength-fill";
+        strengthBar.appendChild(strengthFill);
+        strengthDiv.appendChild(strengthBar);
+
+        const strengthText = document.createElement("span");
+        strengthText.id = "passphrase-strength-text";
+        strengthDiv.appendChild(strengthText);
+        formDiv.appendChild(strengthDiv);
+
+        /**
+         * Evaluate passphrase strength and return score (0-4) with feedback
+         * @param {string} passphrase
+         * @returns {{score: number, label: string, feedback: string}}
+         */
+        function evaluatePassphraseStrength(passphrase) {
+          if (!passphrase) {
+            return { score: 0, label: "", feedback: "" };
+          }
+
+          let score = 0;
+          const checks = {
+            length8: passphrase.length >= 8,
+            length12: passphrase.length >= 12,
+            length16: passphrase.length >= 16,
+            lowercase: /[a-z]/.test(passphrase),
+            uppercase: /[A-Z]/.test(passphrase),
+            numbers: /[0-9]/.test(passphrase),
+            special: /[^a-zA-Z0-9]/.test(passphrase),
+          };
+
+          // Base score from length
+          if (checks.length8) score += 1;
+          if (checks.length12) score += 1;
+          if (checks.length16) score += 1;
+
+          // Character variety
+          const varietyCount = [
+            checks.lowercase,
+            checks.uppercase,
+            checks.numbers,
+            checks.special,
+          ].filter(Boolean).length;
+          if (varietyCount >= 2) score += 1;
+          if (varietyCount >= 3) score += 1;
+          if (varietyCount >= 4) score += 1;
+
+          // Cap at 4
+          score = Math.min(score, 4);
+
+          // Determine label and feedback
+          let label, feedback;
+          if (score <= 1) {
+            label = "Weak";
+            feedback =
+              "Add more characters and mix letters, numbers, and symbols.";
+          } else if (score === 2) {
+            label = "Fair";
+            feedback = "Consider adding more length or character variety.";
+          } else if (score === 3) {
+            label = "Good";
+            feedback = "Good passphrase strength.";
+          } else {
+            label = "Strong";
+            feedback = "Excellent passphrase strength!";
+          }
+
+          return { score, label, feedback };
+        }
+
+        // Update strength indicator on input
+        passphraseInput.addEventListener("input", () => {
+          const { score, label, feedback } = evaluatePassphraseStrength(
+            passphraseInput.value
+          );
+
+          // Update fill width and color
+          const strengthClasses = [
+            "strength-weak",
+            "strength-fair",
+            "strength-good",
+            "strength-strong",
+          ];
+          strengthFill.className = "";
+
+          if (score === 0) {
+            strengthFill.style.width = "0%";
+            strengthText.textContent = "";
+          } else {
+            strengthFill.style.width = `${score * 25}%`;
+            strengthFill.classList.add(strengthClasses[Math.min(score - 1, 3)]);
+            strengthText.textContent = `${label} — ${feedback}`;
+          }
+        });
+
+        // Create confirmation input
+        const confirmLabel = document.createElement("label");
+        confirmLabel.setAttribute("for", "export-passphrase-confirm");
+        confirmLabel.innerText = "Confirm Passphrase";
+        formDiv.appendChild(confirmLabel);
+
+        const confirmInput = document.createElement("input");
+        confirmInput.type = "password";
+        confirmInput.id = "export-passphrase-confirm";
+        confirmInput.placeholder = "Confirm passphrase";
+        confirmInput.required = true;
+        confirmInput.setAttribute("aria-required", "true");
+        confirmInput.setAttribute("autocomplete", "new-password");
+        formDiv.appendChild(confirmInput);
+
+        // Create error message paragraph
+        const errorMsg = document.createElement("p");
+        errorMsg.id = "passphrase-error";
+        errorMsg.style.display = "none";
+        formDiv.appendChild(errorMsg);
+
+        // Create submit button
+        const submitButton = document.createElement("button");
+        submitButton.type = "submit";
+        submitButton.id = "encrypt-and-export";
+        submitButton.innerText = "Encrypt & Export";
+        formDiv.appendChild(submitButton);
+
+        // Append the form to the body
+        document.body.appendChild(formDiv);
+
+        // Add submit event listener to the form
+        formDiv.addEventListener("submit", async (event) => {
+          event.preventDefault();
+          const passphrase = passphraseInput.value;
+          const confirmPassphrase = confirmInput.value;
+
+          // Validate minimum passphrase length (8 characters)
+          if (passphrase.length < 8) {
+            errorMsg.innerText =
+              "Passphrase must be at least 8 characters long.";
+            errorMsg.style.display = "block";
+            return;
+          }
+
+          // Validate passphrases match
+          if (passphrase !== confirmPassphrase) {
+            errorMsg.innerText = "Passphrases do not match.";
+            errorMsg.style.display = "block";
+            return;
+          }
+
+          // Hide error message and disable button to prevent duplicate submissions
+          errorMsg.style.display = "none";
+          submitButton.disabled = true;
+
+          let mnemonicBytes;
+          let encryptedBytes;
+          try {
+            // Encode mnemonic to Uint8Array
+            const encoder = new TextEncoder();
+            mnemonicBytes = encoder.encode(mnemonic);
+
+            // Encrypt with passphrase
+            encryptedBytes = await TKHQ.encryptWithPassphrase(
+              mnemonicBytes,
+              passphrase
+            );
+
+            // Convert to base64
+            const encryptedBase64 = btoa(
+              Array.from(encryptedBytes, (b) => String.fromCharCode(b)).join("")
+            );
+
+            // Clear passphrase fields for security before sending message
+            passphraseInput.value = "";
+            confirmInput.value = "";
+            // Reset strength indicator
+            strengthFill.style.width = "0%";
+            strengthFill.className = "";
+            strengthText.textContent = "";
+
+            // Zero out sensitive byte arrays (mutable, so we can wipe them)
+            for (let i = 0; i < mnemonicBytes.length; i++) mnemonicBytes[i] = 0;
+            for (let i = 0; i < encryptedBytes.length; i++)
+              encryptedBytes[i] = 0;
+
+            // Clear the mnemonic closure reference (can't truly zero a JS string, but removes the easy reference)
+            mnemonic = "";
+
+            // Send message up
+            TKHQ.sendMessageUp(
+              "ENCRYPTED_WALLET_EXPORT",
+              encryptedBase64,
+              requestId
+            );
+
+            // Remove the entire form from the DOM — no sensitive material should linger
+            formDiv.remove();
+          } catch (e) {
+            // Zero out sensitive byte arrays if they were created
+            if (mnemonicBytes) {
+              for (let i = 0; i < mnemonicBytes.length; i++)
+                mnemonicBytes[i] = 0;
+            }
+            if (encryptedBytes) {
+              for (let i = 0; i < encryptedBytes.length; i++)
+                encryptedBytes[i] = 0;
+            }
+
+            // Clear passphrase fields for security
+            passphraseInput.value = "";
+            confirmInput.value = "";
+            // Reset strength indicator
+            strengthFill.style.width = "0%";
+            strengthFill.className = "";
+            strengthText.textContent = "";
+
+            errorMsg.innerText = "Encryption failed: " + e.toString();
+            errorMsg.style.display = "block";
+            submitButton.disabled = false;
+          }
+        });
+      }
+
       /**
        * Parse and decrypt the export bundle.
        * The `bundle` param is a JSON string of the encapsulated public
@@ -1585,6 +2063,30 @@ <h2>Message log</h2>
         TKHQ.sendMessageUp("BUNDLE_INJECTED", true, requestId);
       }
 
+      /**
+       * Function triggered when INJECT_WALLET_EXPORT_BUNDLE_ENCRYPTED event is received.
+       * @param {string} bundle
+       * @param {string} organizationId
+       * @param {string} requestId
+       */
+      async function onInjectWalletBundleEncrypted(
+        bundle,
+        organizationId,
+        requestId
+      ) {
+        // Decrypt the export bundle
+        const walletBytes = await decryptBundle(bundle, organizationId);
+
+        // Reset embedded key after using for decryption
+        TKHQ.onResetEmbeddedKey();
+
+        // Parse the decrypted wallet bytes
+        const wallet = TKHQ.encodeWallet(new Uint8Array(walletBytes));
+
+        // Display passphrase form instead of showing the key directly
+        displayPassphraseForm(wallet.mnemonic, requestId);
+      }
+
       /**
        * Function triggered when APPLY_SETTINGS event is received.
        * For now, the only settings that can be applied are for "styles".
diff --git a/export/index.test.js b/export/index.test.js
index 79648fe..dd13277 100644
--- a/export/index.test.js
+++ b/export/index.test.js
@@ -446,4 +446,392 @@ describe("TKHQ", () => {
     };
     expect(TKHQ.validateStyles(allStylesValid)).toEqual(allStylesValid);
   });
+
+  it("encrypts data with passphrase correctly", async () => {
+    const plaintext = new TextEncoder().encode("test mnemonic phrase");
+    const passphrase = "securepassword123";
+
+    const encrypted = await TKHQ.encryptWithPassphrase(plaintext, passphrase);
+
+    // Result should be salt (16) + iv (12) + ciphertext (at least as long as plaintext + auth tag)
+    // Note: Using ArrayBuffer check due to JSDOM cross-realm Uint8Array difference
+    expect(encrypted.buffer).toBeDefined();
+    expect(encrypted.length).toBeGreaterThanOrEqual(16 + 12 + plaintext.length);
+
+    // Salt and IV should be present at the beginning
+    const salt = encrypted.slice(0, 16);
+    const iv = encrypted.slice(16, 28);
+    expect(salt.length).toBe(16);
+    expect(iv.length).toBe(12);
+  });
+
+  it("decrypts data encrypted by encryptWithPassphrase correctly", async () => {
+    const originalText =
+      "abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about";
+    const plaintext = new TextEncoder().encode(originalText);
+    const passphrase = "mySecurePassphrase!";
+
+    // Encrypt
+    const encrypted = await TKHQ.encryptWithPassphrase(plaintext, passphrase);
+
+    // Decrypt
+    const decrypted = await TKHQ.decryptWithPassphrase(encrypted, passphrase);
+
+    // Verify
+    const decryptedText = new TextDecoder().decode(decrypted);
+    expect(decryptedText).toBe(originalText);
+  });
+
+  it("fails to decrypt with wrong passphrase", async () => {
+    const plaintext = new TextEncoder().encode("secret data");
+    const correctPassphrase = "correctPassphrase";
+    const wrongPassphrase = "wrongPassphrase";
+
+    const encrypted = await TKHQ.encryptWithPassphrase(
+      plaintext,
+      correctPassphrase
+    );
+
+    // Attempting to decrypt with wrong passphrase should throw
+    await expect(
+      TKHQ.decryptWithPassphrase(encrypted, wrongPassphrase)
+    ).rejects.toThrow();
+  });
+
+  it("produces different ciphertext for same plaintext (due to random salt/IV)", async () => {
+    const plaintext = new TextEncoder().encode("same plaintext");
+    const passphrase = "samePassphrase";
+
+    const encrypted1 = await TKHQ.encryptWithPassphrase(plaintext, passphrase);
+    const encrypted2 = await TKHQ.encryptWithPassphrase(plaintext, passphrase);
+
+    // Encrypted results should be different due to random salt and IV
+    expect(TKHQ.uint8arrayToHexString(encrypted1)).not.toBe(
+      TKHQ.uint8arrayToHexString(encrypted2)
+    );
+
+    // But both should decrypt to the same plaintext
+    const decrypted1 = await TKHQ.decryptWithPassphrase(encrypted1, passphrase);
+    const decrypted2 = await TKHQ.decryptWithPassphrase(encrypted2, passphrase);
+
+    expect(new TextDecoder().decode(decrypted1)).toBe("same plaintext");
+    expect(new TextDecoder().decode(decrypted2)).toBe("same plaintext");
+  });
+
+  it("handles encryption of wallet mnemonic end-to-end", async () => {
+    const mnemonic =
+      "suffer surround soup duck goose patrol add unveil appear eye neglect hurry alpha project tomorrow embody hen wish twenty join notable amused burden treat";
+    const passphrase = "strongPassphrase123!";
+
+    // Encode mnemonic to bytes
+    const mnemonicBytes = new TextEncoder().encode(mnemonic);
+
+    // Encrypt
+    const encrypted = await TKHQ.encryptWithPassphrase(
+      mnemonicBytes,
+      passphrase
+    );
+
+    // Convert to base64 (as would be done in displayPassphraseForm)
+    const encryptedBase64 = btoa(
+      Array.from(encrypted, (b) => String.fromCharCode(b)).join("")
+    );
+    expect(typeof encryptedBase64).toBe("string");
+    expect(encryptedBase64.length).toBeGreaterThan(0);
+
+    // Convert back from base64
+    const encryptedFromBase64 = new Uint8Array(
+      atob(encryptedBase64)
+        .split("")
+        .map((c) => c.charCodeAt(0))
+    );
+
+    // Decrypt
+    const decrypted = await TKHQ.decryptWithPassphrase(
+      encryptedFromBase64,
+      passphrase
+    );
+    const decryptedMnemonic = new TextDecoder().decode(decrypted);
+
+    expect(decryptedMnemonic).toBe(mnemonic);
+  });
+});
+
+/**
+ * Tests for passphrase form validation
+ * These tests create the form elements manually and test the validation logic
+ */
+describe("Passphrase Form Validation", () => {
+  let dom;
+  let document;
+  let TKHQ;
+
+  // Helper to create the passphrase form elements (mimics displayPassphraseForm)
+  function createPassphraseForm() {
+    const formDiv = document.createElement("form");
+    formDiv.id = "passphrase-form-div";
+
+    const passphraseInput = document.createElement("input");
+    passphraseInput.type = "password";
+    passphraseInput.id = "export-passphrase";
+    formDiv.appendChild(passphraseInput);
+
+    const confirmInput = document.createElement("input");
+    confirmInput.type = "password";
+    confirmInput.id = "export-passphrase-confirm";
+    formDiv.appendChild(confirmInput);
+
+    const errorMsg = document.createElement("p");
+    errorMsg.id = "passphrase-error";
+    errorMsg.style.display = "none";
+    formDiv.appendChild(errorMsg);
+
+    const submitButton = document.createElement("button");
+    submitButton.type = "submit";
+    submitButton.id = "encrypt-and-export";
+    formDiv.appendChild(submitButton);
+
+    document.body.appendChild(formDiv);
+
+    return { formDiv, passphraseInput, confirmInput, errorMsg, submitButton };
+  }
+
+  // Helper to submit form (triggers validation)
+  function submitForm(elements) {
+    const event = new dom.window.Event("submit", {
+      bubbles: true,
+      cancelable: true,
+    });
+    elements.formDiv.dispatchEvent(event);
+  }
+
+  // Helper to create submit handler that mimics displayPassphraseForm logic
+  function addValidationHandler(elements, mnemonic, onSuccess) {
+    const { formDiv, passphraseInput, confirmInput, errorMsg } = elements;
+
+    formDiv.addEventListener("submit", async (event) => {
+      event.preventDefault();
+      const passphrase = passphraseInput.value;
+      const confirmPassphrase = confirmInput.value;
+
+      // Validate minimum passphrase length (8 characters)
+      if (passphrase.length < 8) {
+        errorMsg.innerText = "Passphrase must be at least 8 characters long.";
+        errorMsg.style.display = "block";
+        return;
+      }
+
+      // Validate passphrases match
+      if (passphrase !== confirmPassphrase) {
+        errorMsg.innerText = "Passphrases do not match.";
+        errorMsg.style.display = "block";
+        return;
+      }
+
+      // Hide error message
+      errorMsg.style.display = "none";
+
+      if (onSuccess) {
+        await onSuccess(passphrase);
+      }
+    });
+  }
+
+  beforeEach(() => {
+    dom = new JSDOM(html, {
+      runScripts: "dangerously",
+      url: "http://localhost",
+      beforeParse(window) {
+        window.TextDecoder = TextDecoder;
+        window.TextEncoder = TextEncoder;
+      },
+    });
+
+    Object.defineProperty(dom.window, "crypto", {
+      value: crypto.webcrypto,
+    });
+
+    document = dom.window.document;
+    TKHQ = dom.window.TKHQ;
+  });
+
+  it("shows error when passphrase is too short", () => {
+    const elements = createPassphraseForm();
+    addValidationHandler(elements, "test mnemonic");
+
+    // Set a passphrase that's too short (< 8 chars)
+    elements.passphraseInput.value = "short";
+    elements.confirmInput.value = "short";
+
+    // Submit form
+    submitForm(elements);
+
+    // Error should be displayed
+    expect(elements.errorMsg.style.display).toBe("block");
+    expect(elements.errorMsg.innerText).toBe(
+      "Passphrase must be at least 8 characters long."
+    );
+  });
+
+  it("shows error when passphrase is exactly 7 characters", () => {
+    const elements = createPassphraseForm();
+    addValidationHandler(elements, "test mnemonic");
+
+    // Set a passphrase that's exactly 7 chars (boundary case)
+    elements.passphraseInput.value = "1234567";
+    elements.confirmInput.value = "1234567";
+
+    submitForm(elements);
+
+    expect(elements.errorMsg.style.display).toBe("block");
+    expect(elements.errorMsg.innerText).toBe(
+      "Passphrase must be at least 8 characters long."
+    );
+  });
+
+  it("accepts passphrase with exactly 8 characters", async () => {
+    const elements = createPassphraseForm();
+    let successCalled = false;
+
+    addValidationHandler(elements, "test mnemonic", async () => {
+      successCalled = true;
+    });
+
+    // Set a passphrase that's exactly 8 chars (boundary case - should pass)
+    elements.passphraseInput.value = "12345678";
+    elements.confirmInput.value = "12345678";
+
+    submitForm(elements);
+
+    // Allow async handler to complete
+    await new Promise((resolve) => setTimeout(resolve, 10));
+
+    expect(elements.errorMsg.style.display).toBe("none");
+    expect(successCalled).toBe(true);
+  });
+
+  it("shows error when passphrases do not match", () => {
+    const elements = createPassphraseForm();
+    addValidationHandler(elements, "test mnemonic");
+
+    // Set mismatched passphrases (both >= 8 chars)
+    elements.passphraseInput.value = "password123";
+    elements.confirmInput.value = "password456";
+
+    submitForm(elements);
+
+    expect(elements.errorMsg.style.display).toBe("block");
+    expect(elements.errorMsg.innerText).toBe("Passphrases do not match.");
+  });
+
+  it("shows length error before mismatch error", () => {
+    const elements = createPassphraseForm();
+    addValidationHandler(elements, "test mnemonic");
+
+    // Set short AND mismatched passphrases
+    elements.passphraseInput.value = "short";
+    elements.confirmInput.value = "diff";
+
+    submitForm(elements);
+
+    // Length error should take precedence
+    expect(elements.errorMsg.style.display).toBe("block");
+    expect(elements.errorMsg.innerText).toBe(
+      "Passphrase must be at least 8 characters long."
+    );
+  });
+
+  it("hides error message on successful validation", async () => {
+    const elements = createPassphraseForm();
+    addValidationHandler(elements, "test mnemonic", async () => {});
+
+    // First trigger an error
+    elements.passphraseInput.value = "short";
+    elements.confirmInput.value = "short";
+    submitForm(elements);
+    expect(elements.errorMsg.style.display).toBe("block");
+
+    // Now enter valid passphrases
+    elements.passphraseInput.value = "validpassword123";
+    elements.confirmInput.value = "validpassword123";
+    submitForm(elements);
+
+    // Allow async handler to complete
+    await new Promise((resolve) => setTimeout(resolve, 10));
+
+    // Error should be hidden
+    expect(elements.errorMsg.style.display).toBe("none");
+  });
+
+  it("accepts empty confirmation when passphrase is too short (length check first)", () => {
+    const elements = createPassphraseForm();
+    addValidationHandler(elements, "test mnemonic");
+
+    // Short passphrase with empty confirmation
+    elements.passphraseInput.value = "short";
+    elements.confirmInput.value = "";
+
+    submitForm(elements);
+
+    // Should show length error, not mismatch
+    expect(elements.errorMsg.innerText).toBe(
+      "Passphrase must be at least 8 characters long."
+    );
+  });
+
+  it("validates with special characters in passphrase", async () => {
+    const elements = createPassphraseForm();
+    let receivedPassphrase = null;
+
+    addValidationHandler(elements, "test mnemonic", async (passphrase) => {
+      receivedPassphrase = passphrase;
+    });
+
+    // Passphrase with special characters
+    const specialPass = "p@$$w0rd!#%^&*()";
+    elements.passphraseInput.value = specialPass;
+    elements.confirmInput.value = specialPass;
+
+    submitForm(elements);
+
+    await new Promise((resolve) => setTimeout(resolve, 10));
+
+    expect(elements.errorMsg.style.display).toBe("none");
+    expect(receivedPassphrase).toBe(specialPass);
+  });
+
+  it("validates with unicode characters in passphrase", async () => {
+    const elements = createPassphraseForm();
+    let receivedPassphrase = null;
+
+    addValidationHandler(elements, "test mnemonic", async (passphrase) => {
+      receivedPassphrase = passphrase;
+    });
+
+    // Passphrase with unicode
+    const unicodePass = "密码🔐secure";
+    elements.passphraseInput.value = unicodePass;
+    elements.confirmInput.value = unicodePass;
+
+    submitForm(elements);
+
+    await new Promise((resolve) => setTimeout(resolve, 10));
+
+    expect(elements.errorMsg.style.display).toBe("none");
+    expect(receivedPassphrase).toBe(unicodePass);
+  });
+
+  it("is case-sensitive when comparing passphrases", () => {
+    const elements = createPassphraseForm();
+    addValidationHandler(elements, "test mnemonic");
+
+    // Same passphrase but different case
+    elements.passphraseInput.value = "Password123";
+    elements.confirmInput.value = "password123";
+
+    submitForm(elements);
+
+    expect(elements.errorMsg.style.display).toBe("block");
+    expect(elements.errorMsg.innerText).toBe("Passphrases do not match.");
+  });
 });