Is my video uploaded to a server to compress it?

No — this runs ffmpeg compiled to WebAssembly, executing entirely inside your browser tab. The Trust Meter confirms nothing is sent over the network during processing.

How long does compression take?

Roughly proportional to video length and your device's CPU — expect it to take a noticeable fraction of the video's own runtime, longer on older hardware.

Why does the tool need to download something first?

The ffmpeg engine itself is a ~30MB WebAssembly module, served from this site (not a third-party CDN). It's fetched once and cached by your browser, so repeat visits skip the download.

No. 03

Video Trimmer & Compressor

Trim a clip and shrink its file size, right in your browser — nothing is uploaded to compress it.

Drop a video, or click to choose

MP4, WebM, MOV, AVI, MKV

Uploaded 0 bytes Loads a ~30MB video engine (ffmpeg) once, then works offline for the rest of the session. (network monitor unsupported in this browser)

How your data is handled: everything above runs inside this browser tab; your file is never uploaded. Loads a ~30MB video engine (ffmpeg) once, then works offline for the rest of the session.

Compressing a video usually means uploading it to a website and waiting in a queue — a bad idea for anything personal, and slow either way. This tool runs a real video encoder (ffmpeg) inside your browser via WebAssembly, so trimming and compressing happen on your own machine.

How to use it

Drop a video file onto the film-strip trimmer.
Drag the trim handles to set an in and out point.
Set a target quality with the compression dial and pick an output format: MP4, WebM, or GIF.
Click Export — the before/after size gauge shows the result, then download it.

Tips & edge cases

Trimming happens before compressing, so cutting a long recording down first is the fastest way to shrink a file — you're not re-encoding footage you don't need.
GIF export is best for short clips under ~10 seconds; GIF has no real compression for motion, so longer exports get large fast.
The encoder runs single-threaded today, so speed is mostly a function of your CPU and the video's length/resolution rather than any browser setting you need to check.

FAQ

Is my video uploaded to a server to compress it?: No — this runs ffmpeg compiled to WebAssembly, executing entirely inside your browser tab. The Trust Meter confirms nothing is sent over the network during processing.
How long does compression take?: Roughly proportional to video length and your device's CPU — expect it to take a noticeable fraction of the video's own runtime, longer on older hardware.
Why does the tool need to download something first?: The ffmpeg engine itself is a ~30MB WebAssembly module, served from this site (not a third-party CDN). It's fetched once and cached by your browser, so repeat visits skip the download.