Transcribe M4A to text
M4A is the format the iPhone Voice Memos app, the Android recorder and most messengers record in. Send the file and you get the same transcript as for any other audio: the text with a start and an end time on every line, speaker labels on request and six export formats. One file is up to 64 MB and 120 minutes, and the free plan needs no card.
Where an M4A file comes from
| Source | What you get | What to do |
|---|---|---|
| iPhone Voice Memos | an .m4a file — AAC audio inside an MP4 container | share the recording to yourself (AirDrop, Files, mail) and upload the file; the whole workflow is on the voice memo page |
| The Android recorder | an .m4a, a .3gp or an .amr file | export it and upload it; we take m4a, wav, mp3, ogg, flac, aac and wma |
| Messenger voice notes | a small .m4a or .ogg | save the voice note as a file and upload that |
| A recorder app on a computer | an .m4a or a .wav | upload it as it is |
| A hardware recorder | a .wav or an .mp3 | upload it as it is |
What we do to the file
M4A is a container with an AAC audio track inside it. The service decodes the container to plain audio before the recognition pass, so what reaches the engine is the same audio it would be for a WAV. Nothing else changes: the limits, the exports, the prices and the accuracy are exactly the same as for any other format.
A phone records at 8 to 22 kHz in mono. The engine takes what it gets, and a cleaner recording is worth more than any setting on our side.
How to transcribe an M4A file
-
Get the file off the phone
Share the recording to yourself and pick it from the file picker on the widget, or send it to the API with
POST /v1/transcripts. -
Set the language, or let the service detect it
Russian or English, or automatic detection — 0.39 s on a short file in our own measurement.
-
Ask for speaker separation when the recording has more than one voice
Switch on “Split by speaker”. The API takes the same switch in the
diarizefield. -
Read it, fix a word, export it
The text, the times and the speaker labels; export to TXT, Markdown, SRT, VTT, CSV or DOCX.
M4A, MP3 and the rest
| Format | Where it comes from | What to know |
|---|---|---|
| MP3 | voice recorders, podcast downloads, anything exported to MP3 | the smallest choice at the same quality; 64 kbps is enough for speech |
| M4A / AAC | iPhone Voice Memos, the Android recorder, messenger voice notes | the same engine; the page on M4A explains how to get the file off the phone |
| WAV | studio exports, dictation apps, hardware recorders | big: 16-bit 16 kHz mono is about 32 KB a second, so ten minutes is about 19 MB |
| MP4 / MOV / WebM | screen recordings, conference recordings, video | the picture is not read; a long video usually has to lose its picture first |
| OGG, FLAC, AAC, WMA | everything else we accept | one file at a time, up to 64 MB and 120 minutes |
What we do not do
We do not read your phone, we do not sync anything and we do not pull files out of messengers. You bring the file, we give you the text. If you want the whole workflow for short recordings, start with the voice memo page.
Put a file on the page and read the first lines.
The widget below is the same one as on the home page: file → transcript with timecodes and speakers → export. The transcript is saved to your account.
Drop an audio or video file
or — mp3, wav, m4a, mp4, up to 64 MB and two hours
Transcription runs under your account: sign in or create a free account.
No account yet? The free plan needs no card. Create a free account or sign in.
Questions this page answers.
Does the iPhone Voice Memos app have to be connected?
No. The service takes files: share the recording to yourself, open the page on the phone and pick the file, or send it from your own code. Nothing on the phone is read by us.
Why is my M4A so small?
AAC is a compressed format. At 64 kbps mono, ten minutes is about 4.8 MB (calculated from the bitrate) and a two-hour recording is about 57.6 MB, which still fits the 64 MB limit.
Can I upload a recording straight from the phone?
Yes. The widget is a web page, so the file picker on the phone works. Pick the recording, press “Transcribe”, and the text comes back on the same page.
Is M4A transcribed better than MP3?
The container does not decide, the audio inside does. At the same bitrate and the same recording the result is the same; a clean 22 kHz recording beats a noisy 128 kbps one.
Do you keep my voice memos?
Until you delete them: the file and the transcript stay in your account, and on the Free plan the transcript is kept for 7 days. Deleted files leave the live system immediately and encrypted backups within 30 days.
Can I transcribe several memos at once?
One file per request. Sixty memos are sixty requests, and on the app the queue shows each of them separately.
Related pages.
The whole workflow for short recordings, and what they cost.
The same for the file a recorder or a podcast download gives you.
Transcribe a phone call recording
What a phone line does to the audio.
Every plan, every limit, in one table.
Upload with drag and drop, the queue and the exports.
The live answer base: 99 questions about the price, the limits, the languages, the exports, the privacy and the API, each with the page of this site it comes from.
Mark Vesyoly, Founder.
Every number on this page comes from the service contract, the pricing page or our own measurements. The author of the page and the publisher of the site are the same person. Questions and corrections: support@transcrib.si.