How to convert M4A to closed captions with Sonix

Sonix converts your audio-to-text using the latest artificial intelligence algorithms—it's fast, easy, beautiful, and affordable. We extract the speech from your M4A file and help you create captions for your videos in minutes.

Convert M4A to captions
Free trial—30 minutes free credit included

How do I accurately convert my M4A files to closed captions? 📋

Sonix uses the latest automated transcription technology to convert your audio files (*.m4a) to closed captions. Follow these six steps and see how magical it is:

Step 1: Create a free Sonix account to start converting your M4A file to a closed caption file

Step 1

Sign up for a free Sonix trial account—includes 30 minutes of free M4A to captions conversion.

Step 2: Upload your M4A files from your computer, Google Drive, Dropbox, or by dragging it on the page.

Step 2

Upload the MPEG-4 Audio File file(s) (*.M4A) from your computer, Dropbox, Google Drive, or by dragging it on the page.

Step 3: Select the language spoken in your M4A file, then click 'Start Transcribing Now.'

Step 3

Choose the language spoken in the uploaded M4A file. We support over 37 different languages including Russian, Chinese, Spanish, and English. Click the 'Start Transcribing Now' button.

Step 4: Sonix does all the work so grab a tasty cupcake. Our servers will extract the audio from your M4A file and convert it to SRT.

Step 4

Sonix will then automatically transcribe the audio from your M4A file and convert it to a simple text format. Grab a cupcake, it will take only a few minutes.

Step 5: Once your M4A was converted to text, you might need to polish up the transcript. Now, you can easily do that with our AudioText Editor.

Step 5

Use the Sonix AudioText Editor to polish your transcript before we convert it to a caption file. Simply type in your browser to correct any words in your transcript.

Step 6: Download a SRT version of your M4A file by clicking Export and selecting 'Subrip caption file (.srt).'

Step 6

Click the 'Export' button. Choose either 'Subrip subtitle file (.srt)' or 'WebVTT file (.vtt)' from the dropdown to download the closed caption version of your M4A file. You can also adjust the character length and time duration length of each caption.

That's it! Your M4A file has now been converted to closed captioning and is ready for the next step in your workflow!🎉

Thousands of customers create closed captions from their M4A files with Sonix 💖

  • Google converts their M4A audio files to closed captions with Sonix
  • Microsoft converts their M4A audio files to closed captions with Sonix
  • NBC Universal converts their M4A audio files to closed captions with Sonix
  • ESPN converts their M4A audio files to closed captions with Sonix
  • Stanford University converts their M4A audio files to closed captions with Sonix
  • Yale University converts their M4A audio files to closed captions with Sonix
  • University of California in Los Angeles (UCLA) converts their M4A audio files to closed captions with Sonix
  • ABC News converts their M4A audio files to closed captions with Sonix
  • Quartz converts their M4A audio files to closed captions with Sonix
  • CNBC converts their M4A audio files to closed captions with Sonix
  • CIBC converts their M4A audio files to closed captions with Sonix
  • Princeton University converts their M4A audio files to closed captions with Sonix

Convert M4A audio or speech to subtitle🔈

Frequently Asked Questions for MPEG-4 Audio File (*.M4A)

What is a M4A file?

An M4A audio file is a lossless audio format (and encoding algorithm) created by Apple and utilized on a variety of Apple products (including iPod, iPhone, iPad, iTunes, and Quicktime products). The m4a codec has been open-sourced so it is quite popular. M4A files are usually encoded with Advanced Audio Coding (AAC) which was originally designed to be the successor to MP3. Both MP3 and M4A files are used for audio-only files, and are both unprotected (free from DRM features). Protected files will have a *.m4p file extension. AAC or M4A files do have better audio quality when compared to MP3 files when encoded at the same bitrate due to some of the codec’s improvements such as compression based on perception and a smaller block size for changing audio sounds and signals.

Does Sonix transcribe audio files with a *.M4A file extension?

Yes, Sonix does automatically transcribe audio files with a .M4A file extension. Sonix is an online audio to text converter. Convert any audio (mp3, m4a, wav, ...) or video (mp4, mov, avi, ...) file to text without installing any software! Sonix quickly and accurately transcribes *.M4A files and converts them to text in a subtitle format.

Know anyone who needs to convert MPEG-4 Audio File (.M4A) to subtitle?

We'd appreciate it if you tell them about Sonix—the best way to convert M4A to subtitle.

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Create closed captions from your MPEG-4 Audio File files with Sonix 🚀

Sonix automatically transcribes and translates your audio and video files in over 37 languages. Easily search, edit, and share your media files. Sonix is an online, fully-automated speech to text service that quickly converts MPEG-4 Audio File files to captions. Fast, accurate, and affordable. Millions of users from all over the world.

Fast, accurate automated transcription

Includes 30 minutes of free transcription

Let our support team help you with all of your automated transcription questions. Pictured: Christine Lee

Transcribe and translate confidently knowing you’re backed by our award-winning team who is ready to answer your questions. Get immediate help by visiting our Help Center, resources, tutorials, and Introduction to Sonix videos.

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