Online Video Compressor (Reduce Video File Size)

Drop a video here
MP4, WebM, MOV, MKV, AVI and M4V, up to about 800 MB per file
Processed in your browser: the video is never uploaded.
Compression settings
7
Processing locally… 0%
Processing locally, please keep this page open.
Done
Download file

Compress local videos with four compression levels or custom codec, resolution, quality, frame rate, and audio settings. Compare original and output sizes and savings after processing. Videos stay in your browser.

Online Video Compression: Reduce File Size While Keeping as Much Quality as Possible

Videos recorded on phones can easily reach hundreds of megabytes, making them difficult to send, upload, or store. This tool re-encodes video directly in the browser to reduce its size while clearly showing how much space is saved. No software installation is required, and the video is never uploaded.

How to Choose the Four Levels

Small File uses CRF 30 and 96 kbps audio to prioritize file size. It is suitable for sending and long-term storage, but visible quality loss is more likely. Recommended uses CRF 26 and 128 kbps audio as a balance between size and quality and is suitable for most situations. Higher Quality uses CRF 22 and 192 kbps audio to preserve more image quality with less aggressive compression. Custom opens advanced settings so you can control the container, video codec, resolution, quality, frame rate, and audio individually.

What Does CRF Mean?

CRF stands for Constant Rate Factor, a quality-based encoding parameter. Lower values generally mean better image quality and larger files, with values around 18 to 28 commonly used for acceptable results. The quality slider in this tool maps levels 1 to 10 to CRF 40 to 18 and displays the corresponding CRF value next to the slider. This avoids ambiguous values such as Quality 7. For more predictable choices, common combinations include CRF 20 for high quality, 23 for general use, 26 for compression, and 30 for aggressive compression.

Resolution, Frame Rate, and Audio

Reducing resolution can often save more space than changing CRF. For example, reducing 1080p to 720p cuts the pixel count by about 55% and can substantially reduce file size while making little difference on phones or chat windows. The tool only scales down proportionally and never enlarges a source video. Frame rate is useful for screen recordings and mostly stationary footage: reducing 60 fps to 30 fps can directly cut the amount of frame data by about half. Audio can be copied directly from the source without re-encoding, re-encoded as AAC at 128 or 192 kbps, or removed completely.

Why Does Compression Take Time?

Compression requires decoding frames and encoding them again, which is computationally intensive. Software encoding in a browser is significantly slower than normal video playback. A one-hour video may therefore take some time, while short clips often finish in seconds to tens of seconds. The page displays progress in real time and allows you to cancel the operation. Keep the page open while processing.

Common Uses

Compress phone videos to a size suitable for messaging or email; reduce course recordings for long-term storage; standardize video materials to 720p for editing; remove audio while keeping the video image; or reduce 60 fps game recordings to 30 fps to save space. All processing takes place on your own device.

Privacy and Data Security

This tool does not use server-side video conversion. The video is read locally through the browser file interface, encoding is performed inside the browser using a WebAssembly sandbox, and the output file is generated and downloaded by the browser. When the page is closed or refreshed, the file reference is released. The video is never uploaded or stored on the server.

How to Choose Compression Settings: Levels, CRF, and Resolution

Select a local video and choose a compression level to start, or open the advanced settings to specify the container, codec, resolution, quality, frame rate, and audio handling. After processing, the tool compares the original and output files and shows the percentage of space saved.
  • Four levels: Small File / Recommended / Higher Quality / Custom, with Recommended as the default (CRF 26 + 128 kbps audio)
  • Custom mode lets you specify the container, video codec, resolution, quality, frame rate, and audio handling
  • The quality slider from 1–10 maps directly to CRF 18–40 and displays the current CRF value in the interface
  • Resolution can remain at the source size or be reduced to 1080p / 720p / 480p / 360p without enlarging the video
  • After processing, the tool shows the original file, output file, and percentage of space saved
  • Videos are read and encoded locally in the browser and are never uploaded; no registration is required
Suitable for reducing large phone videos for sharing, compressing course recordings for archiving, standardizing footage to a target resolution, or reducing bitrate and frame rate. Compression always involves a quality trade-off, so start with the Recommended preset and adjust based on the resulting size and visual quality.
Comments 0
No comments yet. Be the first to comment!
Comment content cannot be empty
0/255