Headers
Behavior
- Send the file as
multipart/form-data. Only the first file in the request is read. - The response body is the converted file itself, sent as an attachment, not JSON. Write it straight to disk.
- The source format is detected from the file’s own bytes, not its name or the declared content type.
- What can become what: PNG, JPG and WebP convert to png, jpeg, webp, avif or gif. GIF converts to png, jpeg, webp, avif or mp4. MP4, MOV and MKV convert to mp4, gif or mp3.
- Video to GIF requires Snipp+ and uses the first 10 seconds only, at 15fps and 480px wide.
- MP4 output is remuxed with
+faststartwhen the source is already H.264, and transcoded otherwise. - Metadata is always stripped. Images are re-encoded without it and videos are written with
-map_metadata -1. JPG orientation is applied to the pixels first, so photos stay the right way up. - Files are capped at 50 MB on the free plan. Snipp+ and Ultra have no per-file cap, the same as
/upload. Conversion runs inside the request, so a large video can take a while to come back. - Rate limited to 10 conversions per minute. Converting does not count toward your weekly upload limit.
- To host the result, pipe it into
POST /upload. Note that avif and mp3 are not accepted upload types, so those two are download-only.