diff --git a/src/apis/audio.ts b/src/apis/audio.ts
index 30f3b03..ddd403c 100644
--- a/src/apis/audio.ts
+++ b/src/apis/audio.ts
@@ -17,7 +17,7 @@ import { SpeechCreateParams } from 'openai/resources/audio/speech';
 import { Stream } from '../streaming';
 import { AUDIO_FILE_DURATION_HEADER } from '../constants';
 import getAudioFileDuration from '../getAudioDuration';
-import { isRunningInBrowser } from '../core';
+import { isFsModuleAvailable } from '../core';
 
 export class Audio extends ApiResource {
   transcriptions: transcriptions;
@@ -78,7 +78,8 @@ export class transcriptions extends ApiResource {
   > {
     // @ts-ignore
     const path = body.file?.path;
-    if (path && this.client.calculateAudioDuration && !isRunningInBrowser()) {
+
+    if (path && this.client.calculateAudioDuration && isFsModuleAvailable()) {
       const duration = await getAudioFileDuration(path);
       if (duration) {
         params = {
@@ -110,7 +111,8 @@ export class translations extends ApiResource {
   ): Promise<any> {
     const body: any = _body;
     const path = body.file?.path;
-    if (path && this.client.calculateAudioDuration && !isRunningInBrowser()) {
+
+    if (path && this.client.calculateAudioDuration && isFsModuleAvailable()) {
       const duration = await getAudioFileDuration(path);
       if (duration) {
         params = {
diff --git a/src/core.ts b/src/core.ts
index dd62504..316baec 100644
--- a/src/core.ts
+++ b/src/core.ts
@@ -59,3 +59,12 @@ export const isRunningInBrowser = () => {
     typeof navigator !== 'undefined'
   );
 };
+
+export const isFsModuleAvailable = () => {
+  try {
+    require('fs');
+    return true;
+  } catch (e) {
+    return false;
+  }
+};
diff --git a/src/getAudioDuration.ts b/src/getAudioDuration.ts
index 49d75a6..c75fd29 100644
--- a/src/getAudioDuration.ts
+++ b/src/getAudioDuration.ts
@@ -1,6 +1,6 @@
-import { isRunningInBrowser } from './core';
+import { isFsModuleAvailable } from './core';
 
-const isBrowser = isRunningInBrowser();
+const fsAvailable = isFsModuleAvailable();
 
 let fs: any;
 let open: any;
@@ -8,7 +8,8 @@ let read: any;
 let stat: any;
 let close: any;
 
-if (!isBrowser) {
+// Check if we're in Node.js AND fs module is available
+if (fsAvailable) {
   try {
     fs = require('fs');
     const { promisify } = require('util');
@@ -27,7 +28,8 @@ if (!isBrowser) {
  * Uses optimized file reading to avoid loading entire files into memory
  */
 async function getAudioFileDuration(filePath: string): Promise<string | null> {
-  if (isBrowser || !fs) {
+  // Only proceed if we're in Node.js, fs is available, and fs module loaded successfully
+  if (!fsAvailable || !fs) {
     return null;
   }