How do I accurately convert my GSM files to closed captions? 
Sonix uses the latest automated transcription technology to convert your audio files (*.gsm) to closed captions. Follow these six steps and see how magical it is:
Step 1
Sign up for a free Sonix trial account—includes 30 minutes of free GSM to captions conversion.
Step 2
Upload the Global System for Mobile Audio File file(s) (*.GSM) from your computer, Dropbox, Google Drive, or by dragging it on the page.
Step 3
Choose the language spoken in the uploaded GSM file. We support over 50 different languages including Russian, Chinese, Spanish, and English. Click the 'Start Transcribing Now' button.
Step 4
Sonix will then automatically transcribe the audio from your GSM file and convert it to a simple text format. Grab a cupcake, it will take only a few minutes.
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
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 GSM file. You can also adjust the character length and time duration length of each caption.
That's it! Your GSM 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 GSM files with Sonix 
Frequently Asked Questions for Global System for Mobile Audio File (*.GSM) to subtitle 
What is a GSM file?
GSM is a compressed audio stream that is primarily used by cell phones. GSM files are designed for telephone-quality audio use in Europe and stores audio mainly for telephone quality voice. It makes for a good balance between size of file and quality retention with data around 96KB per minute. GSM is primarily used for voicemail storage or to record phone conversations that will be played back later.
Does Sonix transcribe audio files with a *.GSM file extension?
Yes, Sonix does automatically transcribe audio files with a .GSM file extension. Sonix is an online audio to text converter. Convert any audio (gsm, mp3, m4a, wav, ...) or video (mp4, mov, avi, ...) file to text without installing any software! Sonix quickly and accurately transcribes *.GSM files and converts them to text in a subtitle format.
Know anyone who needs to convert Global System for Mobile Audio File (.GSM) to subtitle?
We'd appreciate it if you tell them about Sonix—the best way to convert GSM to subtitle.
Other ways to convert your GSM audio files with Sonix
GSM to text
Use the most accurate speech-to-text technology to convert files: GSM to text.
GSM to docx
Accurately transcribe your GSM file to Microsoft Word Format (docx) so you can bring the transcript into your workflow.
GSM to PDF
Easily transcribe your GSM file to Adobe's Portable Document Format (pdf) so you can share them with colleagues.
GSM to subtitles
Create subtitles for your GSM files to make them more accessible for your audience.
GSM to srt
Quickly create subtitles from your GSM files and save them as SRTs, one of the most widely supported subtitle formats.
GSM to VTT
Create more advanced captions for your GSM files by using the latest caption format VTT (Video Text Tracks).
Create closed captions from your Global System for Mobile Audio File files with Sonix 
Sonix automatically transcribes and translates your audio/video files in 50+ languages. Easily search, edit, and share your media files. Sonix is an online, fully-automated speech to text service that quickly converts Global System for Mobile Audio File files to captions. Fast, accurate, and affordable. Millions of users from all over the world.
Includes 30 minutes of free transcription
