Features
Video resizer
Resize a video to 4K, 1080p, 720p, 480p, or a custom resolution — aspect-ratio locked by default, entirely in-browser.
What it does
Changes the pixel dimensions of a video. Frames are decoded, resized using high-quality bilinear filtering, and re-encoded into the target format.
Common preset sizes:
- 4K (3840×2160) — for cinema-quality output. Requires a high-bitrate source to look useful.
- 1080p (1920×1080) — standard web video.
- 720p (1280×720) — smaller files, fine for tutorials and talking-head content.
- 480p (854×480) — minimum viable video size; good for very low bandwidth targets.
- Custom — enter your own width / height.
Aspect-ratio lock
On by default. Entering one dimension auto-computes the other so the video is not stretched. Turn the lock off only if you genuinely want anamorphic distortion.
If you need a different aspect ratio but no stretch, use the Video canvas extender to add letterbox / pillarbox padding instead.
Quality vs. file size
Downsampling (e.g. 4K → 1080p) is essentially free quality-wise — there is no detail to lose because the encoder bitrate constraint dominates anyway. The resulting file is much smaller because you have fewer pixels to encode.
Upsampling (e.g. 720p → 1080p) is geometric scaling — it does not invent detail. For genuine quality improvement when upscaling, use the Video upscaler, which uses Lanczos resampling tuned for video.
Codec choice
Default output is WebM (VP9). MP4 (H.264) available if you need it.
Privacy
All processing in your browser. No upload.