OPUSOpus
A modern, very efficient audio codec for both voice and music. WhatsApp and Telegram voice messages are recorded in Opus.
- Compression
- Lossy
Convert Opus to MP3
Turn your Opus files into MP3 files in seconds. Conversion happens in your browser, so your files are never uploaded to a server.
- Files never uploaded
- Free, no sign-up
- No queue
OPUS4F67675300020000
MP34944330400000000
The first bytes of a file often reveal its real format.
or drop them here. You can also paste an image (Ctrl+V).
Free · No sign-up · No upload
Files
These sample files are generated on the page. Convert them to try it out, or add your own.
How to convert Opus to MP3
- 01
Add your Opus files
Click “Choose Opus files” or drop them on the page. You can add several at once.
- 02
Check the MP3 format
MP3 is already selected. Choose the bitrate, from 128 to 320 kbps.
- 03
Convert and download
Click “Convert”, then download your MP3 file. With several files, grab everything at once as a ZIP.
Opus to MP3: what to know
Opus files mostly come from voice messages: WhatsApp saves them as .opus, Telegram as .ogg with the same codec. Opus was designed to keep a voice clear at very low bitrates, whereas MP3 opens in just about every player and transcription tool. Since Opus works at 48 kHz, the sound is resampled to 44.1 kHz, and a message recorded in mono stays mono.
The MP3 keeps the original file name. On Android, WhatsApp voice notes are named PTT followed by the date, for example PTT-20240115-WA0003.opus, so once converted they remain easy to sort by day, which is handy for archiving a series of messages in order. The quality, however, stays that of the message: switching to MP3 will not make the voice any clearer.
Opus vs MP3: what’s the difference?
MP3MPEG-1 Audio Layer III
The most universal audio format. Its compression shrinks files a lot while keeping good listening quality, and it plays on every device.
- Compression
- Lossy
Opus to MP3: frequently asked questions
Where are WhatsApp voice messages stored on an Android phone?
In internal storage, in the “WhatsApp Voice Notes” folder, found under Android/media/com.whatsapp/WhatsApp/Media on recent Android versions. The file names start with PTT. On an iPhone there is no direct access: use WhatsApp’s share option on the voice message, then “Save to Files”.
Why is the MP3 bigger than the original voice message?
Opus compresses speech very efficiently at low bitrates, while the lowest MP3 setting offered here is 128 kbps. The file therefore grows noticeably without gaining any quality. Choose 128 kbps: for a mono voice it is already more than enough, and the MP3 stays small enough to send by email.
Are my Opus files uploaded to the internet?
No. The file is read and converted by your browser, on your device. Nothing is sent to a server, and nothing is kept after you close the page.
Does converting Opus to MP3 reduce quality?
MP3 is a lossy format. At the default bitrate (192 kbps) the difference is inaudible to most listeners; choose 320 kbps for the best quality.
How many Opus files can I convert?
As many as you like, for free and without signing up. Add them all, then download the results one by one or in a single ZIP. The maximum size depends on your device and browser, with a few caps that protect its memory (for example 20,000 files per archive or 5 million filled cells per workbook: see the home page FAQ); a file over one of them is not converted, and a message says so.
Does it work on iPhone and Android?
Formatomat is designed for recent browsers on computers, iPhone and Android, with no app to install. A conversion the browser cannot do (a format it cannot read or write) is refused with a message that says so.