Private ffmpeg conversion
Convert AVI to MP4
Modernize short legacy AVI files as MP4 for phones, websites, and editors. AVI to MP4 requires a full re-encode here, so expect patience for anything beyond a small clip.
Files
No files selected yet.About AVI and MP4 conversion
AVI files often come from older cameras, capture cards, Windows tools, or archives with codecs that modern apps do not like. MP4 with H.264 video and AAC audio is a more practical handoff format for everyday playback and uploads.
This direction is not a quick container swap. The browser ffmpeg engine decodes the legacy streams and writes new MP4-compatible media, which means HD transcodes may run around real time or slower depending on the machine.
Because ffmpeg.wasm works inside the tab and keeps media data in memory, the converter refuses inputs over 512 MB and is scoped to short clips. The one-time same-origin engine load is roughly 31 MB and is reused by audio and video jobs in the queue.
Does this upload my files?
No. Everything on this page runs locally in your browser, so your files are never uploaded to a server. Close the tab and nothing is left behind. It even keeps working if you go offline after the page loads.
This is true for every tool on this site. Curious how that works? Read how browser-side processing works.
FAQ
Why convert AVI to MP4?
MP4 is easier to open on current phones, browsers, editors, and upload forms than many old AVI files.
Can AVI to MP4 avoid re-encoding?
No. This pair writes new H.264 and AAC streams, so the clip is fully processed rather than just renamed.
Why are long AVI files a bad fit?
Browser transcoding is CPU-heavy and memory-bound, so long HD clips can take a long time or hit the input cap.