diff --git a/common/src/main/java/dev/cel/common/internal/ProtoAdapter.java b/common/src/main/java/dev/cel/common/internal/ProtoAdapter.java
index 3eed49257..c1a096930 100644
--- a/common/src/main/java/dev/cel/common/internal/ProtoAdapter.java
+++ b/common/src/main/java/dev/cel/common/internal/ProtoAdapter.java
@@ -139,7 +139,7 @@ public Object adaptProtoToValue(MessageOrBuilder proto) {
     // If the proto is not a well-known type, then the input Message is what's expected as the
     // output return value.
     WellKnownProto wellKnownProto =
-        WellKnownProto.getByTypeName(typeName(proto.getDescriptorForType()));
+        WellKnownProto.getByTypeName(typeName(proto.getDescriptorForType())).orElse(null);
     if (wellKnownProto == null) {
       return proto;
     }
@@ -280,7 +280,7 @@ private BidiConverter fieldToValueConverter(FieldDescriptor fieldDescriptor) {
    * considered, such as a packing an {@code google.protobuf.StringValue} into a {@code Any} value.
    */
   public Message adaptValueToProto(Object value, String protoTypeName) {
-    WellKnownProto wellKnownProto = WellKnownProto.getByTypeName(protoTypeName);
+    WellKnownProto wellKnownProto = WellKnownProto.getByTypeName(protoTypeName).orElse(null);
     if (wellKnownProto == null) {
       if (value instanceof Message) {
         return (Message) value;
@@ -326,8 +326,7 @@ private static boolean isWrapperType(FieldDescriptor fieldDescriptor) {
       return false;
     }
     String fieldTypeName = fieldDescriptor.getMessageType().getFullName();
-    WellKnownProto wellKnownProto = WellKnownProto.getByTypeName(fieldTypeName);
-    return wellKnownProto != null && wellKnownProto.isWrapperType();
+    return WellKnownProto.isWrapperType(fieldTypeName);
   }
 
   private static int intCheckedCast(long value) {
diff --git a/common/src/main/java/dev/cel/common/internal/WellKnownProto.java b/common/src/main/java/dev/cel/common/internal/WellKnownProto.java
index 476891181..78041e3be 100644
--- a/common/src/main/java/dev/cel/common/internal/WellKnownProto.java
+++ b/common/src/main/java/dev/cel/common/internal/WellKnownProto.java
@@ -36,8 +36,8 @@
 import com.google.protobuf.UInt64Value;
 import com.google.protobuf.Value;
 import dev.cel.common.annotations.Internal;
+import java.util.Optional;
 import java.util.function.Function;
-import org.jspecify.annotations.Nullable;
 
 /**
  * WellKnownProto types used throughout CEL. These types are specially handled to ensure that
@@ -46,77 +46,79 @@
  */
 @Internal
 public enum WellKnownProto {
-  ANY_VALUE("google.protobuf.Any", Any.class.getName()),
-  DURATION("google.protobuf.Duration", Duration.class.getName()),
-  JSON_LIST_VALUE("google.protobuf.ListValue", ListValue.class.getName()),
-  JSON_STRUCT_VALUE("google.protobuf.Struct", Struct.class.getName()),
-  JSON_VALUE("google.protobuf.Value", Value.class.getName()),
-  TIMESTAMP("google.protobuf.Timestamp", Timestamp.class.getName()),
+  ANY_VALUE("google.protobuf.Any", Any.class),
+  DURATION("google.protobuf.Duration", Duration.class),
+  JSON_LIST_VALUE("google.protobuf.ListValue", ListValue.class),
+  JSON_STRUCT_VALUE("google.protobuf.Struct", Struct.class),
+  JSON_VALUE("google.protobuf.Value", Value.class),
+  TIMESTAMP("google.protobuf.Timestamp", Timestamp.class),
   // Wrapper types
-  FLOAT_VALUE("google.protobuf.FloatValue", FloatValue.class.getName(), /* isWrapperType= */ true),
-  INT32_VALUE("google.protobuf.Int32Value", Int32Value.class.getName(), /* isWrapperType= */ true),
-  INT64_VALUE("google.protobuf.Int64Value", Int64Value.class.getName(), /* isWrapperType= */ true),
-  STRING_VALUE(
-      "google.protobuf.StringValue", StringValue.class.getName(), /* isWrapperType= */ true),
-  BOOL_VALUE("google.protobuf.BoolValue", BoolValue.class.getName(), /* isWrapperType= */ true),
-  BYTES_VALUE("google.protobuf.BytesValue", BytesValue.class.getName(), /* isWrapperType= */ true),
-  DOUBLE_VALUE(
-      "google.protobuf.DoubleValue", DoubleValue.class.getName(), /* isWrapperType= */ true),
-  UINT32_VALUE(
-      "google.protobuf.UInt32Value", UInt32Value.class.getName(), /* isWrapperType= */ true),
-  UINT64_VALUE(
-      "google.protobuf.UInt64Value", UInt64Value.class.getName(), /* isWrapperType= */ true),
+  FLOAT_VALUE("google.protobuf.FloatValue", FloatValue.class, /* isWrapperType= */ true),
+  INT32_VALUE("google.protobuf.Int32Value", Int32Value.class, /* isWrapperType= */ true),
+  INT64_VALUE("google.protobuf.Int64Value", Int64Value.class, /* isWrapperType= */ true),
+  STRING_VALUE("google.protobuf.StringValue", StringValue.class, /* isWrapperType= */ true),
+  BOOL_VALUE("google.protobuf.BoolValue", BoolValue.class, /* isWrapperType= */ true),
+  BYTES_VALUE("google.protobuf.BytesValue", BytesValue.class, /* isWrapperType= */ true),
+  DOUBLE_VALUE("google.protobuf.DoubleValue", DoubleValue.class, /* isWrapperType= */ true),
+  UINT32_VALUE("google.protobuf.UInt32Value", UInt32Value.class, /* isWrapperType= */ true),
+  UINT64_VALUE("google.protobuf.UInt64Value", UInt64Value.class, /* isWrapperType= */ true),
   // These aren't explicitly called out as wrapper types in the spec, but behave like one, because
   // they are still converted into an equivalent primitive type.
 
-  EMPTY("google.protobuf.Empty", Empty.class.getName(), /* isWrapperType= */ true),
-  FIELD_MASK("google.protobuf.FieldMask", FieldMask.class.getName(), /* isWrapperType= */ true),
+  EMPTY("google.protobuf.Empty", Empty.class, /* isWrapperType= */ true),
+  FIELD_MASK("google.protobuf.FieldMask", FieldMask.class, /* isWrapperType= */ true),
   ;
 
-  private static final ImmutableMap<String, WellKnownProto> WELL_KNOWN_PROTO_MAP;
+  private static final ImmutableMap<String, WellKnownProto> TYPE_NAME_TO_WELL_KNOWN_PROTO_MAP =
+      stream(WellKnownProto.values())
+          .collect(toImmutableMap(WellKnownProto::typeName, Function.identity()));
 
-  static {
-    WELL_KNOWN_PROTO_MAP =
-        stream(WellKnownProto.values())
-            .collect(toImmutableMap(WellKnownProto::typeName, Function.identity()));
-  }
+  private static final ImmutableMap<Class<?>, WellKnownProto>
+      CLASS_TO_NAME_TO_WELL_KNOWN_PROTO_MAP =
+          stream(WellKnownProto.values())
+              .collect(toImmutableMap(WellKnownProto::messageClass, Function.identity()));
 
-  private final String wellKnownProtoFullName;
-  private final String javaClassName;
+  private final String wellKnownProtoTypeName;
+  private final Class<?> clazz;
   private final boolean isWrapperType;
 
+  /** Gets the fully qualified prototype name (ex: google.protobuf.FloatValue) */
   public String typeName() {
-    return wellKnownProtoFullName;
+    return wellKnownProtoTypeName;
   }
 
-  public String javaClassName() {
-    return this.javaClassName;
+  /** Gets the underlying java class for this WellKnownProto. */
+  public Class<?> messageClass() {
+    return clazz;
   }
 
-  public static @Nullable WellKnownProto getByTypeName(String typeName) {
-    return WELL_KNOWN_PROTO_MAP.get(typeName);
+  public static Optional<WellKnownProto> getByTypeName(String typeName) {
+    return Optional.ofNullable(TYPE_NAME_TO_WELL_KNOWN_PROTO_MAP.get(typeName));
   }
 
-  public static boolean isWrapperType(String typeName) {
-    WellKnownProto wellKnownProto = getByTypeName(typeName);
-    if (wellKnownProto == null) {
-      return false;
-    }
+  public static Optional<WellKnownProto> getByClass(Class<?> clazz) {
+    return Optional.ofNullable(CLASS_TO_NAME_TO_WELL_KNOWN_PROTO_MAP.get(clazz));
+  }
 
-    return wellKnownProto.isWrapperType();
+  /**
+   * Returns true if the provided {@code typeName} is a well known type, and it's a wrapper. False
+   * otherwise.
+   */
+  public static boolean isWrapperType(String typeName) {
+    return getByTypeName(typeName).map(WellKnownProto::isWrapperType).orElse(false);
   }
 
   public boolean isWrapperType() {
     return isWrapperType;
   }
 
-  WellKnownProto(String wellKnownProtoFullName, String javaClassName) {
-    this(wellKnownProtoFullName, javaClassName, /* isWrapperType= */ false);
+  WellKnownProto(String wellKnownProtoTypeName, Class<?> clazz) {
+    this(wellKnownProtoTypeName, clazz, /* isWrapperType= */ false);
   }
 
-  WellKnownProto(String wellKnownProtoFullName, String javaClassName, boolean isWrapperType) {
-    this.wellKnownProtoFullName = wellKnownProtoFullName;
-    this.javaClassName = javaClassName;
+  WellKnownProto(String wellKnownProtoFullName, Class<?> clazz, boolean isWrapperType) {
+    this.wellKnownProtoTypeName = wellKnownProtoFullName;
+    this.clazz = clazz;
     this.isWrapperType = isWrapperType;
   }
 }
diff --git a/common/src/main/java/dev/cel/common/values/ProtoCelValueConverter.java b/common/src/main/java/dev/cel/common/values/ProtoCelValueConverter.java
index 16d1a8956..16f5cc215 100644
--- a/common/src/main/java/dev/cel/common/values/ProtoCelValueConverter.java
+++ b/common/src/main/java/dev/cel/common/values/ProtoCelValueConverter.java
@@ -107,7 +107,7 @@ public CelValue fromProtoMessageToCelValue(MessageOrBuilder message) {
     }
 
     WellKnownProto wellKnownProto =
-        WellKnownProto.getByTypeName(message.getDescriptorForType().getFullName());
+        WellKnownProto.getByTypeName(message.getDescriptorForType().getFullName()).orElse(null);
     if (wellKnownProto == null) {
       return ProtoMessageValue.create((Message) message, celDescriptorPool, this);
     }
diff --git a/common/src/test/java/dev/cel/common/internal/WellKnownProtoTest.java b/common/src/test/java/dev/cel/common/internal/WellKnownProtoTest.java
index 7fc6eabfd..bb75a341a 100644
--- a/common/src/test/java/dev/cel/common/internal/WellKnownProtoTest.java
+++ b/common/src/test/java/dev/cel/common/internal/WellKnownProtoTest.java
@@ -16,8 +16,10 @@
 
 import static com.google.common.truth.Truth.assertThat;
 
+import com.google.protobuf.FloatValue;
 import com.google.testing.junit.testparameterinjector.TestParameterInjector;
 import com.google.testing.junit.testparameterinjector.TestParameters;
+import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 
@@ -53,7 +55,12 @@ public void isWrapperType_withTypeName_false(String typeName) {
   }
 
   @Test
-  public void getJavaClassName() {
-    assertThat(WellKnownProto.ANY_VALUE.javaClassName()).isEqualTo("com.google.protobuf.Any");
+  public void getByClass_success() {
+    assertThat(WellKnownProto.getByClass(FloatValue.class)).hasValue(WellKnownProto.FLOAT_VALUE);
+  }
+
+  @Test
+  public void getByClass_unknownClass_returnsEmpty() {
+    assertThat(WellKnownProto.getByClass(List.class)).isEmpty();
   }
 }