Compress MP4 Video Online

Make an MP4 video much smaller without uploading it. Pick a quality, or type the size you need and let the tool reach it.

How to use the Compress MP4 tool

  1. Choose your video, or drag it onto the box.
  2. Pick a quality level, or switch to "Target size" and type the size you need.
  3. Press Compress video and wait for the progress bar to finish.
  4. Compare the before and after sizes, preview the result and download it.

About this tool

MP4 is the most common video container, and most MP4 files are H.264 with AAC audio. That is already an efficient codec, so compression here means lowering the bitrate (and optionally the resolution or frame rate) until the file is as small as you need.

Choose a quality preset for a quick result, or switch to Target size and enter a limit such as 25 MB. The tool picks the bitrate for you, lowers the resolution automatically if the target is tight, and re-encodes with your browser's hardware encoder. You can also limit the frame rate or remove the audio.

Why use ToolsCrow for this

  • Quality or exact size. Two ways to control the result.
  • Never bigger than needed. The bitrate is capped by the source.
  • Private. Runs on your device.
  • No watermark. Free with no account.

Good to know

  • Lossy compression removes detail; the smaller the target, the softer the picture.
  • Audio codecs your browser cannot decode (for example AC-3 or DTS) are dropped, and you will be told.

Frequently asked questions

Is my video uploaded to a server?

No. Everything runs inside your browser tab using your own device's video hardware. Your file is never sent to ToolsCrow or anyone else, which also means there is no waiting for an upload and it keeps working if your connection drops after the page has loaded.

Is it really free? Is there a watermark?

It is free with no sign-up, no watermark and no daily limits. The only limits are the ones your device sets: memory and processing power.

How large a video can I use?

Because the video is processed on your device, the limit is your device's memory rather than a server quota. Phone clips of several hundred MB are fine on most devices, and desktop computers usually handle 1 to 2 GB. Files over about 4 GB are not supported.

Which browsers work best?

Current Chrome, Edge and Safari (16.4 or newer, including iPhone and iPad) work best because they include the WebCodecs video engine. Recent Firefox versions work for many files. Older browsers fall back to a much slower real-time mode or may not work at all.

How much can I shrink a video?

Phone and screen-recording footage often shrinks 60 to 90 percent with little visible loss. Videos that were already compressed for the web may only shrink a little.

Why does my result have Opus audio instead of AAC?

Some browsers (for example Chrome on Linux) cannot encode AAC audio. When that happens the tool saves Opus audio instead and tells you. Opus plays in Chrome, Firefox, Edge, VLC and recent Safari; if you need AAC everywhere, run the tool in Chrome or Edge on Windows or macOS, or in Safari.

Why is it fast, or slow, on my device?

Speed depends on whether your device has hardware video encoding, which most phones and laptops from the last several years do. A short phone clip usually finishes in seconds. Very long, 4K or high-frame-rate videos take longer, and the progress bar shows an estimate.

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⭐ User Reviews

5
★★★★★
1 review
Usman Chaudhry
Nov 5, 2026
★★★★★
📌 Compress WebM for web embedding
WebM files bohat heavy thay website ke lye. Compress kiye without quality loss. Page load ab fast hai. Must-have tool.