Convert Video
Pick the file, pick the format, download. When the source codec already fits the target format, the tool swaps the container alone — a near-instant operation that loses not one bit of quality. When it does not fit, it re-encodes and says so. All inside the tab, with the video going nowhere.
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How it works
mp4 and mov usually carry the same H.264, and converting between them is literally changing the wrapper: the command is -c copy and it takes seconds even on a half-hour file. webm is another story, because it needs VP9 or AV1, and neither comes out of an mp4 without re-encoding. VP9 in WebAssembly is slow — expect several minutes for a few minutes of video, and prefer it for short web-bound clips. If your only goal is a smaller file, compressing by CRF does that better than changing format.
- Output to mp4 (H.264), webm (VP9) and mov (H.264)
- Container swap with no re-encode when the codecs are compatible
- CRF quality control when a re-encode is unavoidable
- Before and after size comparison