Resize Video – Free Online Tool
Change video resolution to any size. Scale videos up or down while maintaining aspect ratio.
Example Output
Resizes to your chosen resolution or scale percentage, preserving aspect ratio. Bicubic / Lanczos filter for sharp downscales.
screen-recording.mp4 (1920×1080, 1080p, ~78 MB)
What is Resize Video?
Resize any video to a specific resolution (1080p, 720p, 480p) or a percentage of the original — useful for shrinking 4K clips to a web-friendly 1080p, generating multiple sizes for adaptive streaming, or simply reducing file size. Bicubic / Lanczos scaling preserves sharpness on downscales.
Why use this tool?
- No registration, account, or installation required
- No API keys to manage and no rate limits to monitor
- 100% free with no hidden costs or daily limits
- First-load downloads the WASM core once (~30 MB), then subsequent edits are fast
- No video upload — clips of any length stay on your local machine
How to use
- Upload your video file
- Enter new width and/or height
- Choose to maintain aspect ratio or not
- Click "Resize Video" and download
Examples
4K → 1080p web version
A 280 MB 4K screen recording becomes a 78 MB 1080p clip — looks identical on most displays at a fraction of the size.
Multiple sizes for ABR
Generate 1080p, 720p, and 480p renditions from one source for adaptive bitrate streaming on your own site.
50% downscale
A 1920×1080 input scales to 960×540 (quarter the pixels) in one click — quick for previews and thumbnails.
Common use cases
- Reducing 4K footage for web playback
- Producing multiple resolutions for adaptive streaming
- Shrinking video to fit upload limits
- Generating previews / thumbnails from full-resolution sources
- Standardising mixed-resolution footage to one target size
Troubleshooting
- Output looks soft
- Switch the scaler from "bilinear" to "Lanczos" or "bicubic" for sharper downscales. Bilinear is fast but blurs detail.
- Aspect ratio looks squashed
- Enable "preserve aspect ratio" — otherwise entering both width and height stretches the video. Set only one, and let the other compute.
- File size barely changed
- Resizing alone doesn't guarantee smaller files if bitrate stays high. Combine with re-encoding (CRF 23-28) for big savings.
Frequently Asked Questions
Downscaling generally preserves quality well. Upscaling may result in some quality loss depending on the original resolution.
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