How to use the Compress MP4
- Choose the MP4.
- Choose a compression level or set a target size.
- Optionally lower the resolution.
- Compress and download.
Why MP4s get so big
Phones record at very high bitrates so that every frame looks perfect, often 15–50 Mbps. For sharing, 2–5 Mbps at 1080p looks almost the same. Re-encoding at a sensible bitrate is where the big savings come from.
Good to know
Compression uses H.264 (x264, "veryfast" preset) with either a quality target (CRF) or a calculated bitrate for target sizes. Audio is re-encoded to AAC. The file is never uploaded, so even private videos can be compressed safely.
Supported files
MP4, MOV, MKV, WEBM, AVI, WMV, FLV, M4V, 3GP, 3G2, MPEG, MPG, TS, MTS, M2TS, VOB, OGV, MXF, ASF, DIVX, F4V, SWF, DV, MOD, TOD, WTV, RM and RMVB video, with H.264, HEVC, VP8, VP9, MPEG-4, MPEG-2, WMV, Theora and other codecs. AV1 videos cannot be read in the browser yet. Files up to 1 GB each.
Frequently asked questions
My MP4 got bigger
That happens when the video was already efficiently compressed. Try "Strong" or a lower resolution.
How much does the Compress MP4 cost?
Nothing. It is free with no registration, no watermark and no limit on how many files you convert.
Do you keep a copy of my files?
We never receive them. All processing happens on your device, so there is nothing for us to store or delete.
Does it work on iPhone and Android?
Yes, in Safari, Chrome and other modern mobile browsers. Short files work best on phones; for long or high-resolution videos a computer is faster.