Audio and video file formats for transcription: one reference table
6 min Which audio and video formats a browser can transcribe, what each carries inside, what is discarded before the speech model hears it, and when converting is worth it.
Formats.
SRT, VTT, plain text and the rules that make subtitle files work everywhere.
Captions for TikTok, Reels and Shorts: what each platform accepts
8 min Subtitles for Reels, TikTok and Shorts: what YouTube's help pages document, what we could not verify, and how to cut cues short enough to read on a phone.
Subtitles and accessibility: what the WCAG captions rules require
8 min A plain guide to the WCAG captions rules: which success criteria are Level A, which are AA, what captions must contain, and how to produce the file.
How to convert SRT to VTT, plain text or a document
8 min Converting SRT to VTT, VTT back to SRT, or a subtitle file into plain text or a document: the exact edits, what each one loses, and when to use an editor.
How to make an SRT file (and the format rules that break players)
8 min The exact SRT format, three ways to make a file, the timing rules broadcasters use, and the five small mistakes that make YouTube or VLC reject it.
SRT vs VTT vs plain text: which export do you need?
8 min SRT vs VTT vs plain text, settled: what a cue is, why SRT carries no styling, what breaks in the wrong player, and which export to take for each job.
How to transcribe a WebM file to text, the format your browser picked for you
8 min Transcribe WebM to text in the browser. What Opus audio, a missing duration and a screen recording with no audio track mean for the file you were handed.
How to transcribe an M4A file to text, and what M4A actually is
8 min Transcribe M4A to text in your browser. What Apple's extension really means, where M4A files come from, and why a purchased track refuses to open.
How to transcribe a WAV file to text, and why the size is not the quality
8 min Transcribe WAV to text in the browser, with the arithmetic behind a 600 MB hour and why an uncompressed studio file reaches the model as 16 kHz mono.
How to transcribe an MP3 to text, and what the bitrate costs you
8 min Transcribe MP3 to text in your browser, and see what bitrate, mono or stereo and re-encoding really cost you once the audio is mixed down to 16 kHz mono.