Video Optimizer
Reduce video file size while maintaining good quality, processed in your browser with ffmpeg
Compress Video Online - Reduce Video File Size Free
EzyIMG's video compressor reduces video file size by re-encoding with H.264 or VP9 at a quality level you control. Whether you need to shrink a large MP4 for an email attachment, reduce a clip for web embedding, or compress footage for social media without obvious quality loss, this tool handles it all. Upload your MP4, WebM, MOV, MKV, or AVI, choose a quality preset or dial in a CRF value manually, optionally cap the resolution, and download the compressed result in seconds.
All compression runs entirely in your browser using WebAssembly. Your video is never uploaded to any server. There is no account required, no watermark added to the output, and no file size limits enforced by EzyIMG. Your footage stays on your device from start to finish, making this tool safe for confidential or personal video content.
How to Use
- 1
Upload your video
Drop an MP4, WebM, MOV, MKV, or AVI file into the upload area.
- 2
Choose a quality preset or set CRF manually
Use a quick preset (Social Media, Web, High Quality, Maximum Compression) or drag the CRF slider to set compression manually.
- 3
Optionally reduce the resolution
Uncheck 'Keep Original' and drag the width slider to cap the output resolution. Combining lower resolution with a higher CRF multiplies the file size savings.
- 4
Click Compress
Click Optimize Video to start. Processing runs locally in your browser using ffmpeg.wasm.
- 5
Download the result
Compare the before and after file sizes and download the compressed video.
Key Features
- →CRF 28 gives good compression with acceptable quality, ideal for social media uploads and web embeds.
- →Lower CRF means higher quality and a larger file; higher CRF means smaller file with more compression.
- →Reducing resolution (e.g. from 1080p to 720p) before compressing multiplies the file size savings significantly.
- →This tool runs entirely in your browser. No upload, no account, and no watermark on the output.
- →Use WebM (VP9) output for web embedding; it is typically 20–30% smaller than MP4 at the same visual quality.
- →For maximum reduction, combine this tool with Video Resize to shrink dimensions before compressing.
Frequently Asked Questions
Is Compress Video on EzyIMG completely free?
Yes, 100% free. No account required, no watermark on the output, and no limits on how many videos you compress.
Does EzyIMG upload my video?
No. All compression runs using WebAssembly (ffmpeg.wasm) directly in your browser. Your video never leaves your device.
What formats does Compress Video support?
Input: MP4, WebM, MOV, MKV, AVI, and most other video formats. Output: MP4 (H.264) or WebM (VP9).
How much can I reduce a video file size without losing quality?
Using a CRF of 24–28, most videos can be reduced by 40–70% with no perceptible quality loss at normal viewing sizes on screens.
What is CRF in video compression?
CRF (Constant Rate Factor) is a quality-based encoding setting. Values range from 0 (lossless) to 51 (maximum compression). CRF 18–23 is high quality; CRF 24–28 is good for sharing; CRF 29+ is heavy compression.
Last updated: June 2026