Resize Video for TikTok, Reels & YouTube
One click to the right aspect ratio for every platform.
Free · No upload · No sign-up · No watermark
How to resize a video for social media
- 01
Open your video
Drop in any landscape, square or vertical video.
- 02
Choose a format
Pick a preset like TikTok 9:16 or Instagram 4:5, then drag to reframe or add a blurred background.
- 03
Download
Export a correctly sized MP4 that uploads without black bars or unexpected cropping.
Why use Cutlia for this
Platform presets
TikTok, Reels, Shorts, YouTube, Instagram feed, X and LinkedIn sizes built in.
Crop or fit
Fill the frame by cropping, or fit the whole video with a blurred or solid background.
Follows people automatically
Turn on “Follow people” and AI on your device keeps the person in frame, shot by shot — two side by side can share a split screen.
Reposition the frame
Or drag the video inside the new frame yourself to keep faces and action in view.
Free crop
Need a custom size? Draw any crop rectangle you like.
Frequently asked questions
What size is a TikTok video?
TikTok, Instagram Reels and YouTube Shorts all use a 9:16 vertical format, typically 1080×1920 pixels. Choose the 9:16 preset and Cutlia handles the rest.
Can it keep the person in frame automatically?
Yes. Choose “Follow people” and Cutlia finds the people in each shot on your device and moves the frame with them. Nothing is uploaded, and you can switch to Manual anytime.
Can I avoid cutting off part of my video?
Yes. Use the “fit” mode to keep the entire picture and fill the empty space with a blurred copy of the video or a solid color.
Is my video uploaded to a server?
No. Cutlia processes your video directly in your browser using WebAssembly and your device's hardware. The file never leaves your computer or phone, so it stays completely private.
Is it really free?
Yes. Cutlia is free to use with no account, no trial and no watermark on your export. The site is paid for by the ads on it, and your files never leave your device.
Made for
Each one is this tool, set up for the job — and it still opens any video.
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