Video Compress

Tool Guide

Introduction

Video Compress is a free online video compression tool that supports MP4, AVI, MPG, MOV, FLV, 3GP, WEBM, MKV, and WMV formats. Powered by FFmpeg.wasm, all processing happens locally in your browser—your video files are never uploaded to any server.

Core Features

1. Resolution Preserved: Video resolution stays unchanged; only bitrate is adjusted.
2. Multiple Format Support: MP4, AVI, MPG, MOV, FLV, 3GP, WEBM, MKV, WMV — 9 formats total.
3. Adjustable Ratio: 5%~95% custom compression ratio, with 30%/40%/50%/60%/80%/90% preset options.
4. Batch Processing: Compress up to 5 video files at once.
5. Pure Browser Processing: FFmpeg.wasm handles everything locally; no server upload.

How to Use

Step 1: Drag and drop or click to upload video files. Multiple files can be selected at once.

Step 2: Choose the compression ratio (slider or preset buttons). Default is 80%.

Step 3: Click "Compress All" and wait for processing. First-time use requires loading the FFmpeg engine (~30MB).

Step 4: Click "Download" for individual files, or "Download All (ZIP)" for a batch download.

Compression Principle

Video compression works by adjusting the video bitrate. Lower bitrate produces a smaller file but lower quality. This tool calculates a target bitrate from the original video's bitrate and the selected ratio, then re-encodes the video using FFmpeg to achieve the target size. Resolution remains unchanged.

FAQ

Q: Will video quality degrade after compression?

A: Yes. The lower the ratio, the smaller the file, but the greater the quality loss. We recommend starting at 80% and lowering it gradually if the quality is acceptable.

Q: Which input formats are supported?

A: MP4, AVI, MPG, MOV, FLV, 3GP, WEBM, MKV, and WMV — 9 formats total.

Q: Will the video resolution change?

A: No. This tool only adjusts the bitrate; resolution stays the same.

Q: What is the maximum file size?

A: 100MB per file, up to 5 files per batch.

Q: Is my video uploaded to any server?

A: No. All processing is done locally in your browser via FFmpeg.wasm. Your video files never leave your device.