diff --git a/firebase-ai/CHANGELOG.md b/firebase-ai/CHANGELOG.md
index 3244c980674..dd818c29cec 100644
--- a/firebase-ai/CHANGELOG.md
+++ b/firebase-ai/CHANGELOG.md
@@ -5,6 +5,7 @@
 * [changed] Introduced the `Voice` class, which accepts a voice name, and deprecated the `Voices` class.
 * [changed] **Breaking Change**: Updated `SpeechConfig` to take in `Voice` class instead of `Voices` class.
     * **Action Required:** Update all references of `SpeechConfig` initialization to use `Voice` class.
+* [fixed] Fix incorrect model name in count token requests to the developer API backend
 
  
 # 16.0.0
diff --git a/firebase-ai/src/main/kotlin/com/google/firebase/ai/common/Request.kt b/firebase-ai/src/main/kotlin/com/google/firebase/ai/common/Request.kt
index 7e54ad1f629..ebc3db7f282 100644
--- a/firebase-ai/src/main/kotlin/com/google/firebase/ai/common/Request.kt
+++ b/firebase-ai/src/main/kotlin/com/google/firebase/ai/common/Request.kt
@@ -18,6 +18,7 @@
 package com.google.firebase.ai.common
 
 import com.google.firebase.ai.common.util.fullModelName
+import com.google.firebase.ai.common.util.trimmedModelName
 import com.google.firebase.ai.type.Content
 import com.google.firebase.ai.type.GenerationConfig
 import com.google.firebase.ai.type.ImagenImageFormat
@@ -57,7 +58,7 @@ internal data class CountTokensRequest(
       CountTokensRequest(
         generateContentRequest =
           generateContentRequest.model?.let {
-            generateContentRequest.copy(model = fullModelName(it))
+            generateContentRequest.copy(model = fullModelName(trimmedModelName(it)))
           }
             ?: generateContentRequest
       )
diff --git a/firebase-ai/src/main/kotlin/com/google/firebase/ai/common/util/util.kt b/firebase-ai/src/main/kotlin/com/google/firebase/ai/common/util/util.kt
index d8181b38030..1fc71f6c4ff 100644
--- a/firebase-ai/src/main/kotlin/com/google/firebase/ai/common/util/util.kt
+++ b/firebase-ai/src/main/kotlin/com/google/firebase/ai/common/util/util.kt
@@ -23,3 +23,5 @@ package com.google.firebase.ai.common.util
  */
 internal fun fullModelName(name: String): String =
   name.takeIf { it.contains("/") } ?: "models/$name"
+
+internal fun trimmedModelName(name: String): String = name.split("/").last()