Reduces MP4, MOV, and WebM video file sizes with a configurable CRF 20–40 slider (default 28, libx264 fast preset), plus a GIF mode with color-palette control. Videos never leave your device — compression runs locally in your browser with FFmpeg WASM.
Runs on FFmpeg
Content reviewed October 2026 · About Toolzum
Compress multiple videos with one shared CRF setting (18 high quality, 23 default, 28 smaller, 35 maximum) encoded libx264 medium preset with 128k AAC audio. Studios batch 20 daily uploads at CRF 28 — local FFmpeg WASM, 2 free batches a day.
Convert MP4/WebM to GIF animations. Videos up to 250MB. Videos never leave your device — compression and conversion run locally in your browser with FFmpeg WASM.
Grade videos with 18 filters across Color, Artistic, Blur, and Lighting (grayscale, sepia, pixelate, gaussian blur, vignette, brightness/contrast/saturation) plus a live still-frame preview. Export MP4, WebM, or GIF — local FFmpeg work, unlimited saves.
Compress one animated GIF with FFmpeg: colors slider 2–256 (default 128), Floyd or no dithering, loss tolerance 0–100 (above 50 flips lossless to lossy), and optional duplicate-frame removal (mpdecimate, off by default). Output fps locks to 10; result shows KB and -% and saves as <name>-compressed.gif.
Shrink JPG, PNG, and WebP photos with an Image Quality slider (10–100%, default 80%) plus a Resolution Scale slider, shown in Before/After panels with exact KB and -% savings. Single-image uploads up to 50MB — local library work, unlimited saves.
A CRF slider (20–40, default 28) encoded with libx264 on the fast preset for video, and a color-palette slider (32–256 colors, palettegen/paletteuse) for GIF mode. Lower CRF = larger file at higher quality.
CRF (Constant Rate Factor) controls quality. Lower CRF = higher quality/larger file. The slider runs 20 (better quality) to 40 (smaller file): 22 and under reads high quality, around 28 is balanced, 32 and up is visibly compressed.
MP4, MOV, WebM, and MKV video inputs (GIF mode accepts animated GIFs). Output is MP4 for video or optimized GIF. The tool uses FFmpeg for encoding.
There is no pre-compression preview — the CRF label reads High Quality (22 and under), Balanced, or Low Quality (32 and up) as you drag, and the result panel reports the exact % smaller after compression.
No. All compression runs locally in your browser using FFmpeg WASM. Your video never leaves your device.
Bulk Video Compressor
Compress multiple videos with one shared CRF setting (18 high quality, 23 default, 28 smaller, 35 maximum) encoded libx264 medium preset with 128k AAC audio. Studios batch 20 daily uploads at CRF 28 — local FFmpeg WASM, 2 free batches a day.
Video Format Converter
Convert between MKV, MP4, MOV, WebM, and AVI video formats. Pick any input and output format from the dropdown — your files never leave your device.
Video Trimmer
Cut start/end segments from any video with fast stream-copy trimming in your browser (keyframe-aligned, no re-encode). Remove a 45-second cold open from a 10-minute upload — local FFmpeg work, unlimited saves.