Drop an iPhone, Mac or camera.mov and get back a clean H.264/AAC MP4 that plays and uploads everywhere. Real FFmpeg transcoding with faststart for instant playback: all on your device, never uploaded, no watermark, no sign-up.
MOV to MP4 re-encodes QuickTime .mov clips from iPhones, Macs and cameras into universally compatible H.264/AAC MP4 with faststart for instant playback. A real FFmpeg transcode in the browser, not a rename, with broad-compatibility yuv420p pixels, an in-page preview and one-click download. Free, and nothing leaves your device.
This MOV-to-MP4 converter runs a full FFmpeg build compiled to WebAssembly directly in your browser and re-encodes your QuickTime clip's video to H.264 and its audio to AAC inside an MP4 container, the format that plays and uploads virtually everywhere. MOV is what an iPhone, a Mac screen recording or many DSLR and mirrorless cameras hand you: excellent for capture, but awkward for sharing. Windows Media Player and plenty of desktop players stutter or refuse it, some editors and CMS uploaders reject the container outright, and messaging apps often won't preview it. MP4 is the safe lingua franca (every browser, phone, editor, projector and upload form takes it) so converting once ends the ritual of a clip that plays fine on your Mac but breaks the moment you send it. The tool writes the MP4 with `-movflags +faststart`, which moves the index to the front of the file so it starts playing before it has fully downloaded, exactly what you want for the web, email and streaming previews. It also normalizes the pixel format to yuv420p, the profile that keeps H.264 playable on the widest set of hardware decoders instead of only in the app you recorded with. Because everything is client-side there is no upload wait and no privacy tradeoff: personal videos, unreleased footage and confidential screen recordings never leave your machine, and there is no server to store, log or leak them. Drop the MOV, watch a determinate progress bar track the re-encode, and the finished MP4 plays right in the page so you can confirm the picture and audio survived before you download. Be honest with yourself about the cost: this is a genuine re-encode, not a rename, so H.264 in single-threaded WebAssembly is noticeably slower than a native encoder: a short clip converts in seconds while a long or 4K one takes real time behind the progress bar. When your problem is simply that a.mov won't play, won't upload, or won't preview where you need it, drop it here and get a clean, compatible MP4 back, entirely in the browser.
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Drag a QuickTime.mov onto the workspace, or click to browse. The clip is probed locally for its duration and dimensions. Nothing is uploaded.
Click Convert to MP4. FFmpeg loads once (a one-time download), then re-encodes the video to H.264 and audio to AAC with faststart, tracked by a live progress bar.
The finished MP4 plays right in the page with its exact file size, so you can confirm the picture and audio came through cleanly.
Save the MP4, or reset and drop another clip. Everything stays in the browser from start to finish.
Your MOV's video is re-encoded to H.264 and its audio to AAC inside a proper MP4 container, a genuine transcode that plays on the widest set of players, phones and editors, not just a renamed.mov.
The MP4 is written with +faststart, moving its index to the front so it begins playing before the whole file downloads: ideal for the web, email previews and streaming.
MP4 is the format Windows players, messaging apps, CMS uploaders and editors all accept, convert once and stop fighting a.mov that only works on your Mac.
Output is normalized to yuv420p, the H.264 profile hardware decoders and older devices handle best, so the MP4 doesn't play only in the app you recorded it with.
The finished MP4 plays right in the tool with its exact file size, so you can confirm the picture and sound survived the round-trip before you save or send it.
FFmpeg runs as WebAssembly on your device. Your MOV is never uploaded, stored or logged: safe for personal videos, unreleased footage and private screen recordings.
An iPhone or Mac.mov that a Windows PC, a web form or a messaging app rejects becomes an MP4 that just works. No more re-recording or asking someone to switch players.
Many editors, CMSs and social uploaders assume MP4. Convert on-device and give them exactly the container they want, without a round-trip through a third-party server.
Unlike upload-based converters, nothing leaves your device. A personal video, an unreleased capture or a confidential screen recording is transcoded locally. There is no server that ever sees it.
Get a real H.264/AAC MP4 without desktop software, a login or a stamped-on logo. Just a browser tab you can close when you're done.
From quick one-off fixes to daily workflows, see how people put this tool to use.
Convert an iPhone or Mac screen-recording.mov into an MP4 so a friend, colleague or client on Windows can open it in any player: encoded locally so a personal video stays private.
Some editors and older projects assume MP4. Transcode a camera .mov on-device to a broadly compatible H.264 MP4 you can drop straight onto the timeline without a codec fight.
When a social platform, ad manager or CMS won't take .mov, convert your QuickTime capture to MP4 in the browser and upload exactly the format it expects.
A macOS screen capture is a .mov that many chat apps won't preview. Turn it into an MP4 with faststart so it plays inline the moment your teammate opens it.
Accepts MOV, and produces MP4, all processed locally in your browser.
Convert video between MP4, WebM, MOV, AVI, MKV and GIF in your browser with FFmpeg. Pick a target format, tune MP4 quality, preview the result and download. Nothing is uploaded.
Compress video in your browser with FFmpeg, shrink MP4, MOV, WebM and MKV files with a simple quality slider, see the exact bytes and percentage saved next to a live preview, then download. Nothing is uploaded.
Convert MP4 to WebM (VP9) in your browser: a leaner, royalty-free format that streams natively in modern browsers. Tune the quality, preview the result and download. Nothing is uploaded.
Cut and trim video online in your browser, drag a visual timeline to set exact start and end points, preview the selection, and download the clip. No uploads, no account, no watermark.
Turn a video into a high-quality animated GIF right in your browser. Pick a start, duration, frame rate and width, get a two-pass palette for clean color, then preview and download. Nothing is uploaded.
Convert AVI to MP4 (H.264/AAC) in your browser: the universal format that plays on phones, browsers, social and editors. Real transcoding with web-ready faststart, preview and download. Nothing is uploaded.
Go deeper on the concepts behind the mov to mp4.
MOV is Apple's QuickTime container built for editing. MP4 is the cross-platform standard for sharing. Here's when each format is the right call.
Read the comparisonH.265 halves file size at the same quality but needs more support and power, H.264 plays everywhere. Here's when each codec wins for video.
Read the comparisonHit a snag? Here are quick fixes for the issues people run into most.
This is a real H.264 re-encode, not a rename, and single-threaded WebAssembly FFmpeg is meaningfully slower than a native encoder. Long clips and 4K footage are the worst case. Trim to just the part you need first, close other heavy tabs, and expect real time for anything more than a few seconds.
Most iPhone and camera MOVs are already H.264 or HEVC, so re-encoding to H.264 can occasionally land a touch larger depending on the source bitrate. If size matters more than pure compatibility, run the result through the Video Compressor to bring it down with a quality dial.
If the source used an unusual audio codec the AAC re-encode can occasionally drift. Try a different clip, or if the source is HEVC/ProRes, note that these heavy codecs stress the WASM engine: trimming to a shorter range first usually resolves both sync and memory issues.
The first conversion downloads the FFmpeg WebAssembly core (~31 MB) once, then caches it. Give it a moment on the first run. Later conversions in the same session start immediately.
Trim to just the seconds you need before converting: encode time scales with length, so a shorter clip finishes far faster.
MP4 is the safe choice for sharing. Keep the original .mov only if you specifically need the QuickTime container for a Mac-native workflow.
If the result is bigger than you'd like, send it through the Video Compressor afterward to trade a little quality for a smaller file.
4K and HEVC/ProRes MOVs are the heaviest to transcode in the browser, convert on a machine with some CPU and RAM headroom.
Convert one clip at a time. Single-threaded WASM handles a single re-encode best rather than several at once.
Recent updates and improvements to the mov to mp4.
Initial release: browser-side MOV-to-MP4 conversion via WebAssembly FFmpeg, re-encoding video to H.264 and audio to AAC with +faststart, plus a live progress bar, in-page preview and download. Nothing is uploaded.
Normalized output to the yuv420p pixel format for broader hardware playback, and added a before/after size delta on the result.
Sharpened the honest guidance around WASM re-encode speed on 4K and HEVC/ProRes sources, and improved memory handling for larger MOV files.
Your MOV is decoded and re-encoded to MP4 entirely in your browser using FFmpeg compiled to WebAssembly. It is never uploaded to any server. Nothing is stored, logged or transmitted, so you can safely convert personal videos, unreleased footage and private screen recordings. The FFmpeg core is fetched once from this site (same-origin) and cached. Your media stays on your device. Close the tab and every trace is gone.
Free, private and instant. MOV to MP4 runs right in your browser.
