Resize Video
4K is overkill for Slack, but 360p looks bad on a phone — pick a target resolution and we'll scale your video preserving aspect ratio, no math required.
Resize your video
Sign in to run this tool — 100 free credits on signup.
FFmpeg flags used by this tool
Quick reference for what each parameter actually does.
- -vf scale=-2:H
- Scale filter. -2 = auto-compute width, keeping aspect ratio and rounding to an even number (codec requirement).
- -vf scale=W:H
- Force exact width and height. Use only if you actually want to distort.
- flags=lanczos
- Lanczos resampling. Sharper than the default bilinear, especially when downscaling.
- -c:v libx264 -crf 23
- H.264 at quality 23 — sweet spot for visually lossless re-encoding.
- -c:a copy
- Skip audio re-encoding. Resize doesn't touch the audio track, so just copy it through.
- -preset fast
- Encoding speed knob. fast keeps wait time short with minimal size penalty.
How it works
- 01
Upload or paste a URL
Drop a video, or paste a public URL. Up to 5 GB.
- 02
Pick the target resolution
1080p for archive, 720p for social, 480p for previews, 360p when bandwidth is tight.
- 03
Scale in the cloud
We use Lanczos resampling for sharpness, and only downscale (upscaling doesn't add detail).
- 04
Download the result
Aspect ratio preserved automatically. Files auto-expire after 7 days.
FAQ
What's the difference between 1080p and 4K?
1080p (1920×1080) has ~2 megapixels per frame; 4K (3840×2160) has ~8 megapixels — 4× the data. For phone screens and Slack, you don't see the difference. Files are about 4× smaller at 1080p.
Will it stretch my video?
No. We use scale=-2:height, which auto-computes width to preserve aspect ratio. A 16:9 source stays 16:9, a 9:16 vertical video stays 9:16.
Can I upscale a 480p video to 1080p?
Technically yes, but it won't add detail — the pixels get interpolated, which can look worse than the original. Only useful if a platform requires a minimum resolution.
Why not just keep the original size?
Resolution drives file size. Halving each dimension is a 4× file size cut, often with no visible difference on phones/laptops. Storage and bandwidth add up fast.
Which resolution for which platform?
YouTube/Vimeo: 1080p+. TikTok: 1080×1920 (vertical). Instagram feed: 1080×1080 (square) or 1080×1350. Slack/email: 720p is plenty.
Can I do this from code?
Yes — toggle the API view above to see the exact request, or check docs for curl / Node / Python.
Related video tools
Resize in code
Same /v1/tasks endpoint as every other tool. Drop the curl below into a script.
View API docscurl -X POST https://api.ffhub.io/v1/tasks \
-H 'Authorization: Bearer YOUR_API_KEY' \
-H 'Content-Type: application/json' \
-d {
"command": "-i https://you.com/in.mp4 -vf scale=-2:720 -c:v libx264 -crf 23 -preset fast -c:a copy out.mp4"
}