How to Compress a Video with Compress Video Online

Updated

Compress Video Online is a browser-based tool that shrinks video files to a size you specify, with optional trimming and format conversion. It runs entirely in your browser using HTML5 and FFMPEG JS, so your video is not uploaded to a server. It is free, requires no login or email, and adds no watermark. You can use it if you have a reasonably new browser and a video in one of the supported formats.

What you need before starting

  • A supported video file: MP4, WEBM, MOV, FLV, 3GP, M4V, MPG, MPEG, MKV, AVI, WMV, MV, DV, ASF, or 3G2.
  • A newer version of a desktop browser. The tool works on Windows, Linux, and Mac without installing software.
  • Enough local storage for the output file, since the compressed video is saved to your device.

Note that some formats may need conversion processing first, which takes extra time.

Step-by-step: compressing your video

1. Load the video file

Click the file selection button and choose your video, or drag the file onto the page. A video preview appears once the file is loaded.

2. Set the start and end time

Use the Start and End controls to keep only the portion you want. The default covers the entire video, so skip this step if you want to compress the whole clip.

3. Choose the output file size

Set the target size for the output file by dragging the slider or entering a precise value. The tool compresses the video to the size you specify and tries to maintain quality.

4. Set the output format

Choose your preferred output format from the available video formats.

5. Start compression and save

Click the button to begin compression and wait for processing to finish. When it completes, click the save button to store the video on your local device.

What to expect

Aspect Detail
Cost Free, no subscription
Account No login or email required
Watermark None added to output
Processing location In your browser, not on a server
Output Saved to your local device
Systems Windows, Linux, Mac

Common points to watch

  • Format compatibility: Most formats process directly, but a few require conversion first, which adds time.
  • Browser version: An older browser may not support the HTML5 and FFMPEG JS processing.
  • Quality trade-off: Setting a much smaller output size will reduce quality, since the tool balances size against quality.
  • Trimming before compressing: If you only need part of a video, setting the start and end times first avoids compressing footage you will discard.

Because processing happens locally in the browser, your video never leaves your device, which is the main reason this tool is described as secure.