Compress MP4
Make an MP4 smaller without uploading it anywhere. Choose a target size or platform and download a leaner MP4 that still plays everywhere.
Drop a video here, or browse
MP4 · MOV · WebM — compressed right here, nothing uploaded
100% on-device · no signup · no watermark
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Bigger files take longer — your CPU does the work, privately.
Why MP4 files get large — and how to shrink them
MP4 size is driven mostly by bitrate (data per second) and resolution. A 4K or high-bitrate MP4 carries far more data than most uses need. Lowering the bitrate, and downscaling resolution when appropriate, shrinks the file dramatically while keeping it watchable.
This compressor re-encodes to efficient H.264, so the output MP4 plays on every phone, browser and editor — and uploads cleanly to Discord, WhatsApp, email and social.
Pick a target, not a guess
Instead of guessing settings, choose a platform preset or set an exact target size with the slider. The compressor calculates the bitrate needed to hit it from your clip’s length.
Frequently asked questions
How do I compress an MP4 without losing much quality?
Pick the largest target your destination allows and keep the original resolution. Quality drops only as much as the size reduction requires — so don’t over-shrink.
What does the output format look like?
An H.264 + AAC MP4 — the most compatible combination, playable on virtually any device or platform.
Is there a file size limit?
No hard limit, but very large files depend on your device’s memory since everything runs locally. If a huge file fails, try trimming it or compressing in parts.
Are my MP4s uploaded?
No. Compression happens entirely in your browser; nothing is sent to a server.