Three strength levels
Light, recommended and extreme CRF presets — choose your own balance between quality and size.
Shrink video files with H.264 CRF right in your browser — three strength levels, optional downscaling, and a before/after size comparison, with key data processed locally and no watermark.
Privacy-sensitive steps are processed in your browser, and data is destroyed when you close the page.
Clean exports with no watermark or hidden marks added.
Runs right in your desktop or mobile browser — no download needed.
Use it right away — no account required.
Privacy-sensitive steps run in your browser, and data is destroyed when you close the page. Work on private footage, business assets and course recordings with confidence.
Light, recommended and extreme CRF presets — choose your own balance between quality and size.
Cap resolution at 1080p, 720p or 480p — 4K footage gets dramatically smaller for messaging apps and cloud drives.
See the original and compressed sizes side by side the moment it finishes — savings at a glance.
Upload a video file
Pick a compression strength and optionally cap the resolution
Check the size comparison and download the MP4
Use the Compress Video tool in WUJIEE Video Tools: email attachments usually cap around 25MB and WhatsApp around 16MB per video, so pick the recommended CRF level and cap the resolution at 720p. 4K/1080p footage typically compresses to about 1/3–1/10 of its original size, and you see a before/after size comparison immediately. Everything runs with ffmpeg.wasm in your browser, key data processed locally, no sign-up, no watermark, and no server-side size limit.
The light and recommended levels use CRF constant-quality compression that's barely noticeable in everyday viewing. To stay small and sharp, keep the resolution and step up one strength level rather than hard-dropping the resolution; downscaling shrinks size the most (4K to 1080p usually leaves about 1/4 the size) but also lowers sharpness, so balance quality against size for your use.
Yes. WUJIEE Video Tools compiles FFmpeg to WebAssembly (ffmpeg.wasm) and runs it in your browser, with key data processed locally and your data destroyed when you close the page. Unlike tools that make you upload and wait in a server queue, there's no upload wait and no server-side size limit — the trade-off is that speed depends on your device.
Compression re-encodes the whole video, taking roughly 0.5–2× its duration: a 10-minute 1080p clip usually finishes within a few minutes, depending on your device and resolution. Just keep the tab open while it runs.
16 online video tools: compress, trim, convert, turn videos into GIFs, add watermarks and more.
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