HEIC to JPG: Quality, Metadata, and Privacy
A careful HEIC-to-JPG workflow preserves the picture you need without accidentally sharing location data or repeatedly degrading the image.
Read guide →Compress Video
Shrink a video by re-encoding it with H.264 at a quality level you choose, from near-transparent to aggressively small.
Drop a video here or click to browse
MP4, WebM, MOV, AVI — processed locally and never uploaded.
Reviewed 2026-08-15
Free Compress Video – how it works
Compression re-encodes the video with libx264 using constant rate factor, or CRF. Instead of picking a target bitrate and hoping it suits the footage, you pick a quality level and the encoder spends whatever bitrate that level needs. Simple screen recordings end up tiny; detailed camera footage keeps more data because it needs it.
The three presets map to CRF 23, 28, and 35. Lower numbers mean better quality and larger files. CRF 23 is close to visually transparent for most content, 28 is a sensible default when you just need the file smaller, and 35 is for when a size limit matters more than looking good.
Audio is re-encoded to AAC at 128 kbps when the source has a sound track. If it has none, the audio stage is skipped rather than producing a silent track.
How to use Compress Video online
- Add the video. Drop in the file you need to shrink. Screen recordings and phone video usually compress dramatically because they contain a lot of visually simple, repetitive frames.
- Pick a quality level. Choose high quality, balanced, or small file. Start with balanced. If the result is still too large, step down rather than trying to guess a bitrate.
- Encode and compare. Run the compression, then check the output size against the original and watch a few seconds of the result before you throw the source away.
When to use it
- Get a screen recording under an email or chat attachment limit.
- Cut the size of phone footage before backing it up.
- Re-encode an oversized capture so it uploads in reasonable time.
- Normalise a mixed batch of clips to one predictable quality level.
Known limitations
- Everything is bounded by the memory one browser tab can claim. Clips under about 30 seconds are comfortable; multi-minute or 4K footage often stalls or fails with an out-of-memory error.
- Compression always re-encodes, so quality drops a little even at CRF 23. Compressing an already compressed file a second time compounds that loss.
- Browser encoding is single threaded and slower than a native FFmpeg build. Expect a short clip to take noticeably longer here than on the command line.
Frequently asked questions
How much smaller will my video get?
It depends entirely on the source. A screen recording exported at a high bitrate can drop by 80 percent or more at the balanced setting, while footage that was already compressed efficiently may barely shrink at all.
What is CRF and why not just set a bitrate?
CRF asks the encoder to hold a constant perceived quality and vary the bitrate to achieve it. A fixed bitrate wastes data on easy scenes and starves complex ones, so CRF usually gives a better result at the same file size.
Is my video uploaded to a server?
No. FFmpeg is compiled to WebAssembly and runs inside the page, so the file is read from your disk into the tab's own memory. Nothing about the video is sent to opentools.
Will the video still play everywhere after compression?
Yes. The output is H.264 video with AAC audio in an MP4 container, using yuv420p pixel format, which is the most broadly supported combination available.
Why does the first render take longer?
The FFmpeg WebAssembly build is about 31 MB and has to download before the first job can start. The browser caches it afterwards, so later visits skip that step and begin encoding almost immediately.
Related free tools
Browse every video tools, or jump straight to optimize.
Guides related to Compress Video
PNG vs JPG vs WebP vs AVIF: Which Format Should You Use?
There is no universally best image format: photographs, interface graphics, archives, and web pages have different requirements.
Read guide →How to Compress Images for the Web Without Visible Quality Loss
The best web-image optimisation combines right-sized pixels with a suitable format and a quality setting tested on real content.
Read guide →