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MP4 Compressor

Compress MP4 files online and reduce MP4 size. The result stays an MP4 that plays where the original did.

Drop an MP4 file here or click to browse
Select an MP4 video to compress (up to 1 GB)
Loading daily limit...
MP4 files up to 1 GB. Choose H.264, H.265 or AV1, a quality and a resolution.
Your video is compressed on our server and deleted 30 minutes after the result is ready.

Reduce MP4 file size online

This MP4 compressor re-encodes the video track of your MP4 at a lower bitrate and copies the sound across as it is. The result is again an MP4, with H.264 as the default codec, so it plays on the same phones, browsers and TVs as the original. Upload one MP4 up to 1 GB; you can compress 10 videos a day for free.

How much smaller the quality slider makes an MP4

The slider sets the new video bitrate as a share of your file's average bitrate:

QualityNew video bitrateA 200 MB MP4 becomes about
100 100% 200 MB
70 Default 80.5% 161 MB
50 67.5% 135 MB
30 54.5% 109 MB
10 41.5% 83 MB

The sound is copied unchanged on top, so a file with a large share of audio ends up a little bigger than the table, and the video never goes below 250 kbps. Resolution doesn't change these numbers: a lower resolution makes the same bitrate look sharper, which is why it pairs well with a lower slider. Why bitrate decides the size is explained in video bitrate, explained.

Make sure the MP4 still plays

  • Where it plays

    It must play everywhere, including older TVs and editing apps.

    Pick

    Keep H.264. It is saved as standard 8-bit video, even from a 10-bit HDR source, so every player decodes it.

  • Where it plays

    It's for iPhone, Mac and recent Android.

    Pick

    H.265 keeps more detail at the same size. It is tagged hvc1, the form Apple's apps and Safari need to play H.265 in an MP4.

  • Where it plays

    You control the player, for example on your own site.

    Pick

    AV1 is the most efficient and the slowest to encode; older devices may not open it. Which codec does what is in what is a codec.

Every compressed MP4 is also saved web-ready, with its index at the start of the file, so a video on a web page starts playing before it has fully downloaded.

How to compress an MP4

  1. Drop the MP4

    Pick an MP4 up to 1 GB. The panel shows its codec, bitrate, length and resolution.

  2. Set quality, resolution and codec

    Lower the slider for a smaller file, lower the resolution to keep it sharp, and keep H.264 unless you know where it will play.

  3. Compress and download

    Click Compress MP4 and download the result within 30 minutes, before it is deleted.

MP4 compressor questions

No. The audio track is copied exactly as it is. Only if it can't be copied into the new file is it re-encoded, as 192 kbps AAC.

Lower the slider until the file fits the limit, and drop to 720p or 1080p for apps that shrink videos again anyway. The limits and settings per destination are in compress for WhatsApp, email attachment limits and YouTube video compression.

No, this page only takes MP4 and keeps it MP4. Use the video converter to change the format, or the MOV compressor to shrink a MOV as it is.

Near the top of the slider the bitrate barely drops, and the audio is carried over in full. Move the slider down; at 50 the video track gets about two thirds of its old bitrate. A video that was already compressed hard may still come out about the same size, so keep the original then.

Yes: 10 videos a day, up to 1 GB each, with no account and no watermark. The upload is deleted when compression ends, the result 30 minutes later.