Video Compressor
Compress MP4, WebM, MOV, and MKV in your browser. Hit a target file size with H.264, H.265, or AV1, downscale resolution, drop frame rate, strip audio, and preview the result before download.
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Supported: MP4, WebM, MOV, MKV
Max file size: 2GB
Original
Compressed (Preview)
The Video Compressor shrinks an MP4, WebM, MOV, or MKV in your browser while keeping it watchable. Source frames are decoded and re-encoded entirely with the WebCodecs API — clips selected from your device never leave the page, and the compressed result is produced before any network transfer.
Smaller videos upload faster, embed cleanly in chat apps, slip past 25 MB email caps, and stream more reliably on slow connections. Marketers fitting case-study clips into Slack, support teams attaching reproductions to tickets, sales reps sending demo recordings, and creators hitting Twitter / X size caps all benefit from a quick on-the-fly compression pass.
Select Video panel hosts the input mode tabs: upload from device for full local processing, or paste a remote URL when the video already lives on a public server. The card shows the loaded clip's size, duration, and resolution as soon as decode completes.
Compression Settings exposes Basic mode (a single target file size in MB) and Advanced mode (resolution preset, codec selector, video bitrate, frame rate, remove audio toggle, strip metadata toggle).
Original / Compressed previews render side by side after encoding finishes so you can sanity-check the size reduction and quality before downloading.
No. Files chosen from your device are decoded and re-encoded locally in your browser using WebCodecs. The tool only uses the network when you compress a remote URL.
The compressor estimates a video bitrate from your target size, video duration, and audio settings, then re-encodes the video using that bitrate. Real output may differ slightly because codecs adapt bitrate frame to frame.
Encoders honor a minimum quality floor for the chosen codec and resolution. Lower the resolution, drop the frame rate, or remove audio when you need a smaller file.
H.265 (HEVC) and AV1 produce smaller files than H.264 at the same quality, but they take longer to encode and need a modern browser. H.264 is the safest universal choice for sharing on chat apps and email; AV1 wins for archival when both sender and recipient run recent browsers.
Compression always trades quality for size. Aim for the highest target size you can accept and avoid downscaling more than once between tools. Re-encoding from an already compressed source compounds artefacts; always start from the highest-quality master available.
MP4 (H.264, H.265), WebM (VP8, VP9, AV1), MOV, and MKV decoded by WebCodecs. Browser support varies — Chrome and Edge offer the widest codec coverage; Safari supports H.264 and H.265 reliably; Firefox decodes most but encodes a smaller set.
Limited by browser memory rather than a hard cap. Files up to 2 GB usually work on a desktop browser; very long 4K clips may exceed available memory. If a compress fails mid-way, lower the resolution or split the source first.
WebCodecs uses your CPU and GPU; H.265 and AV1 are heavier than H.264, and frames per second of encoding scales with resolution. Closing other tabs, plugging in to power, and switching to H.264 are the quickest wins.
Re-encoding rewrites the container; EXIF-style tags, GPS data, and editor metadata are not carried over unless explicitly preserved. Visible watermarks remain because they are part of the picture itself.