Free Video Compressor Online - Compress MP4, MOV, AVI & All Video Formats Without Upload | Reduce Video File Size
Free Video Compressor Online - Reduce Video File Size Without Quality Loss
Compress almost any video format online free without uploading to any server. Our free video compressor supports MP4, MOV, WebM, AVI, MKV, WMV, FLV, and virtually any video format powered by FFmpeg. Reduce video file size by up to 90% while maintaining excellent quality. Perfect for compressing videos for email, Discord, WhatsApp, or social media. With advanced features like adjustable quality (CRF), resolution control, video trimming, and cropping, you have complete control over the compression process. All processing happens locally on your device using FFmpeg WebAssembly, ensuring your videos remain completely private and secure.
How to Compress Video Online Free
- 1.Upload your video - Click “Choose Video” or drag and drop your MP4, MOV, AVI, MKV, or any video file
- 2.Adjust settings - Set quality level (CRF), change resolution, trim unnecessary parts, or crop the video
- 3.Preview settings - Review the expected file size and duration before compressing
- 4.Compress - Click the “Compress Video” button and wait for processing to complete
- 5.Download - Save your compressed video file to your device
Why Use Our Free Browser-Based Video Compressor?
- 100% Private: No files uploaded to servers
- Completely Free: No limits or subscriptions
- No Waiting: Process videos instantly in your browser
- Works Offline: No internet connection required after page load
- Advanced Features: Trim, crop, resize, and adjust quality
- All Video Formats: Supports MP4, MOV, AVI, MKV, WebM & more
Frequently Asked Questions
Is it safe to compress videos online?
Yes, completely safe. Unlike traditional online compressors, LocalSquash processes your videos entirely in your browser using WebAssembly. Your files never leave your device, are never uploaded to any server, and remain completely private. No one else can access your videos.
How much can I reduce my video file size?
Typically, you can reduce video file size by 50-90% depending on your settings. Using a CRF value of 23-28 provides excellent quality while significantly reducing file size. Lowering the resolution (e.g., from 4K to 1080p) can reduce file size by 70% or more.
What video formats are supported?
We support almost all video formats including MP4, MOV (QuickTime), WebM, AVI, MKV, WMV, FLV, and more. Powered by FFmpeg, LocalSquash can handle virtually any video format. The output is always MP4 with H.264 encoding for maximum compatibility across all devices.
What does CRF mean in video compression?
CRF (Constant Rate Factor) controls video quality. Lower values (18-23) produce higher quality and larger files, while higher values (28-35) produce smaller files with lower quality. We recommend CRF 23-26 for most use cases, offering a good balance between file size and visual quality.
Can I compress 4K videos?
Yes! You can compress 4K videos and optionally downscale them to 1080p or other resolutions for even greater file size reduction. Keep in mind that processing 4K videos requires more time and memory.
Is there a file size limit?
The only limit is your device's available memory. Since processing happens in your browser, very large files (over 2-4GB) may be slow or fail on devices with limited RAM. For best results, we recommend files under 2GB.
Will compressing reduce video quality?
Some quality loss is inevitable with compression, but with proper settings (CRF 23-26), the difference is barely noticeable to the human eye. You can preview the expected file size before compressing to find the right balance for your needs.
Video Compression Tips - Reduce MP4 File Size
- •Start with CRF 23-26 for a good balance between quality and file size
- •Reduce resolution if the video will be viewed on mobile devices or social media
- •Trim unnecessary footage at the beginning and end to reduce file size further
- •Use “veryfast” speed preset for quick compression, or “slower” for better quality at the same file size
- •Lower audio bitrate to 128k for most videos where audio quality is less critical
More Free Online Compression Tools
Need to compress other file types? Try our free browser-based compression tools – no upload required: