Video Resizer
Choose a video, pick a social media preset or custom dimensions, and decide whether to pad with borders or crop to fill; the resized video is encoded in your browser.
- Runs in your browser
- Free to use
About this tool
Every platform wants a different frame. Video Resizer rescales a video in your browser to Instagram, TikTok, Reels, YouTube, LinkedIn and X sizes or any custom dimensions, either padding the picture with coloured borders or cropping it to fill, with FFmpeg doing the work locally and nothing uploaded.
Related: Video Cutter, Resize Image.
How to use it — quick steps
- 01
Add the video
Drop an MP4, WebM or MOV file on the dashed area or choose it; its size appears under the preview.
- 02
Pick the size
A social media preset fills the width and height; choose Custom to type your own dimensions.
- 03
Pad or crop, then resize
Pad keeps the whole picture with coloured borders, Crop fills the frame by trimming the edges.
Key features of this tool
Social presets
Instagram square and portrait, TikTok/Reels/Stories vertical, YouTube/Facebook/LinkedIn landscape and X, or any custom size.
Pad or crop
Letterbox with the colour you choose, or centre-crop to fill the frame; both keep the correct aspect ratio.
FFmpeg in your browser
The real FFmpeg, compiled to WebAssembly and loaded on first use (about 30 MB, then cached); files are processed locally and never uploaded.
Frequently asked questions
Which option should I use for a landscape video on Instagram?
Pad to 1:1 or 4:5 keeps everything visible with borders; Crop to 9:16 fills a Story but trims the sides.
Will the quality change?
The video is re-encoded at a good quality setting; downscaling loses nothing visible, upscaling cannot add detail.
Why is the first use slow?
FFmpeg (about 30 MB) is downloaded the first time and cached; after that it starts in a second or two. Encoding itself runs on one CPU core, so long videos take a while.
Are my files or data uploaded?
No. The tool is plain JavaScript that runs in your browser; the files or data you provide here are never uploaded to our servers.