How do I accurately convert my MP3 files to closed captions? 
Sonix uses the latest automated transcription technology to convert your audio files (*.mp3) 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 MP3 to captions conversion.
Step 2
Upload the MP3 Audio File file(s) (*.MP3) from your computer, Dropbox, Google Drive, or by dragging it on the page.
Step 3
Choose the language spoken in the uploaded MP3 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 MP3 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 MP3 file. You can also adjust the character length and time duration length of each caption.
That's it! Your MP3 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 MP3 files with Sonix 
Frequently Asked Questions for MP3 Audio File (*.MP3) to subtitle 
What is a MP3 file?
MP3 files are one of the most common audio file formats. Almost every player on any platform can open an mp3 file. The MP3 file format is a compressed file format with an intentional loss of audio quality. However, the loss should be negligible for the typical user. It was developed by the Moving Picture Experts Group (MPEG) and uses ‘Layer 3’ audio compression. The audio compression preserves the audio within a normal human’s hearing range, while discarding unnecessary information outside of that range. MP3 files are usually used to store music and audiobooks with ‘near-CD quality sound’ (aka Stereo at 16-bit), but due to the great compression algorithm, the file size is around 1/10th of the WAV or AIF file equivalent. The quality of an MP3 file depends largely on the compression bit rate. Common bit rates are 128, 160, 192, and 256 kbps. And higher bit rates result in higher quality files that also require more disk space. MP3 files are easily handled and transcribed by Sonix, please try to upload higher bitrate quality audio files which will improve your transcript’s accuracy.
Does Sonix transcribe audio files with a *.MP3 file extension?
Yes, Sonix does automatically transcribe audio files with a .MP3 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 *.MP3 files and converts them to text in a subtitle format.
Know anyone who needs to convert MP3 Audio File (.MP3) to subtitle?
We'd appreciate it if you tell them about Sonix—the best way to convert MP3 to subtitle.
Other ways to convert your MP3 audio files with Sonix
MP3 to text
Use the most accurate speech-to-text technology to convert files: MP3 to text.
MP3 to docx
Accurately transcribe your MP3 file to Microsoft Word Format (docx) so you can bring the transcript into your workflow.
MP3 to PDF
Easily transcribe your MP3 file to Adobe's Portable Document Format (pdf) so you can share them with colleagues.
MP3 to subtitles
Create subtitles for your MP3 files to make them more accessible for your audience.
MP3 to srt
Quickly create subtitles from your MP3 files and save them as SRTs, one of the most widely supported subtitle formats.
MP3 to VTT
Create more advanced captions for your MP3 files by using the latest caption format VTT (Video Text Tracks).
Create closed captions from your MP3 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 MP3 Audio File files to captions. Fast, accurate, and affordable. Millions of users from all over the world.
Includes 30 minutes of free transcription
