Compress Video Online

Make a video file typically 50–80% smaller without uploading it anywhere. Pick a preset, compress on your device, and save the result — free, with no monthly limit.

How it works

  1. Upload your video. Drag and drop your video file into DomeScribe or click the upload area to browse your device. MP4, WebM, MOV, AVI, and MKV files are all supported, and the file never leaves your device.
  2. Pick a preset. Choose Small (480p, the biggest reduction), Balanced (720p), or High Quality (1080p). DomeScribe reads the source resolution and bitrate and pre-selects the preset that will actually shrink your file.
  3. Compress your video. Click Compress. The first run loads the ~31 MB in-browser engine (cached afterwards); then the video is downscaled and re-encoded as H.264 on your device. Short clips take seconds; a 10-minute 1080p video a few minutes.
  4. Save the compressed file. When compression finishes, you will see the new file size and how much space you saved. Save the result with a free account — no watermark, no upload.

Video compressor at a glance

Input formats
MP4, WebM, MOV, AVI, MKV
Typical size reduction
Typically 50–80% smaller, depending on the preset and the source
Presets
Small (480p), Balanced (720p), High Quality (1080p)
Privacy
Compression runs in your browser — the video never leaves your device
File size
Limited by your device's memory — up to about 500 MB works reliably
Limits
Free — no monthly limit; runs on your device (a free account is needed to save the file)

Frequently asked questions

Will compressing my video reduce quality?

Compression lowers resolution and bitrate, so some detail is lost — that is where the size saving comes from. At the Balanced and High Quality presets most viewers will not notice on a phone or laptop screen; Small is meant for sending over chat or email where size matters more than detail.

What is the maximum file size I can compress?

There is no server limit because nothing is uploaded. Large files are limited by your device's memory — up to about 500 MB works reliably; bigger files may fail to load on phones or low-memory laptops.

What video formats are supported for compression?

DomeScribe can compress MP4, WebM, MOV, AVI, and MKV files. The output keeps the input container (a MOV comes back as MP4), encoded as H.264 with AAC audio so it plays everywhere.

Is video compression free on DomeScribe?

Yes — free with no monthly limit, because the work runs on your own device rather than on a server. A free account is needed to save the compressed file.

How much can I reduce the file size?

Results vary with the source, but compressed videos are typically 50–80% smaller. Small gives the biggest reduction, High Quality the smallest; videos with high original bitrates or 4K resolution see the largest savings.

What is the best free tool to compress a video for email or Discord?

DomeScribe compresses video free, directly in your browser — the file never gets uploaded to a server, so it is private and there is no upload wait. Use the Small preset to get under common limits like email attachment caps (~25 MB) or Discord's upload limit, or pick Balanced to keep more quality.

Can I compress a video without uploading it anywhere?

Yes — that is exactly how DomeScribe works. Compression runs inside your browser using WebAssembly, so the video never leaves your device. There is no server storing your footage, and it works the same for sensitive personal videos as for work files.

Related tools

  • Compress Audio Files Online — Compress MP3, WAV, FLAC, M4A, and OGG files in your browser. Pick 64–320 kbps and shrink the file — free, no monthly limit, nothing is uploaded.
  • Free Online Video & Audio Converter — Convert video and audio files between formats in your browser — MP4, WebM, MOV, MKV, AVI, MP3, FLAC, WAV and more. Free, no monthly limit, nothing is uploaded.