Does X (Twitter) support WebM files?
WebM is not listed for X Media Studio uploads.
Media Studio documents MP4 and MOV with H.264 video and AAC audio. Convert WebM for that workflow. The Studio specification explicitly excludes native app, ordinary browser and API uploads, whose current WebM behavior has not been tested here.
Convert WebM to MP4 →Source: X Media Studio Library. Media Studio only; not a specification for native app, web or API uploads. Checked 2026-09-12.
Frequently asked
Does X (Twitter) support WebM?
WebM is not listed for X Media Studio uploads. Media Studio documents MP4 and MOV with H.264 video and AAC audio. Convert WebM for that workflow. The Studio specification explicitly excludes native app, ordinary browser and API uploads, whose current WebM behavior has not been tested here.
What format should I convert WebM to for X (Twitter)?
MP4 - a widely supported video container; acceptance also depends on the video and audio codecs inside it. Converting WebM to MP4 runs entirely in your browser with the converter linked below.
Koldflux exports every clip in the format each platform actually wants - no compatibility guesswork, no manual conversion step.
Automate this in Koldflux