Video Compressor
Reduce video file size with a quality/bitrate slider and a before/after size comparison.
What is Video Compressor?
A video size reducer for hitting upload limits, speeding up page loads, and archiving footage without keeping gigabytes around.
How it works
Quality mode maps the slider to a CRF value (constant quality, variable bitrate). Target-size mode solves for the video bitrate from the clip's duration and your chosen audio budget, then applies a two-pass-safe rate cap. Downscaling is applied in the same pass.
- Load your file. Drag a file onto the drop zone or pick one from your device. It is read locally by the browser and never uploaded.
- Set the options. Adjust the handles, format, quality or threshold controls — the preview updates as you change them.
- Process and download. Run the tool, then download the result. Compare the reported before/after size for compressors and converters.
Examples
A 42 MB podcast episode → 9 MB MP3
Trim the intro, normalise to −16 LUFS, and export at 96 kbps mono — a typical interview lands around a fifth of the original size.
A phone video with the wrong orientation
Rotate 90° and the width/height swap in the output, so it plays upright in every player instead of relying on metadata flags.
Common mistakes
Expecting instant encoders
Video encoding runs in single-threaded WebAssembly, so a clip takes roughly its own length (or a little longer) to re-encode. Stream-copy operations are near-instant by comparison.
Re-encoding when a copy would do
Trimming, removing audio and joining same-codec clips can copy streams without re-encoding — pick the copy option when it is offered to avoid any quality loss.
Ignoring the first-load download
The media engine is about 31 MB and is fetched on first use, then cached. The first conversion on a connection is slower than every later one.
Frequently asked questions
Quality slider or target size?
Use the quality slider when you want predictable visual quality; use target size when a platform enforces a limit (for example, a 10 MB email attachment).
Why did the file get bigger?
Compressing an already heavily compressed clip, or setting a very high quality, can re-encode above the original bitrate. The reported before/after figures always show whether you actually saved anything.
What is the fastest way to shrink a video?
Downscale to 720p and drop the audio if you do not need it — resolution is the single biggest lever on file size.