How to use the Custom Video Dimensions tool
- Choose your video.
- Pick the size or format you need. Choose how to fill the frame if the shape changes.
- Press Resize video.
- Check the preview and download the resized file.
About this tool
Some platforms, ad networks and embedded players ask for an exact size: 640×360, 1000×1000, 1280×720. Enter your width and height, and the tool scales the picture to fit. With the aspect ratio locked, changing one number updates the other so nothing is distorted.
Unlock the ratio to choose a different shape. Then decide how to fill it: a blurred version of the video as the background, black bars, cropping the edges to fill the frame, or stretching. Dimensions are rounded to even numbers because video encoders require it.
Why use ToolsCrow for this
- Exact pixels. Any size from 16 to 7680 wide.
- Aspect lock. Auto-calculates the other side.
- Four fill modes. Blur, bars, crop or stretch.
- Private. No upload.
Good to know
- Very large sizes may exceed what your device's encoder supports.
Frequently asked questions
Is my video uploaded to a server?
No. Everything runs inside your browser tab using your own device's video hardware. Your file is never sent to ToolsCrow or anyone else, which also means there is no waiting for an upload and it keeps working if your connection drops after the page has loaded.
Is it really free? Is there a watermark?
It is free with no sign-up, no watermark and no daily limits. The only limits are the ones your device sets: memory and processing power.
How large a video can I use?
Because the video is processed on your device, the limit is your device's memory rather than a server quota. Phone clips of several hundred MB are fine on most devices, and desktop computers usually handle 1 to 2 GB. Files over about 4 GB are not supported.
Which browsers work best?
Current Chrome, Edge and Safari (16.4 or newer, including iPhone and iPad) work best because they include the WebCodecs video engine. Recent Firefox versions work for many files. Older browsers fall back to a much slower real-time mode or may not work at all.
What if my exact size has a different shape from my video?
Unlock "Keep the original aspect ratio" and pick a fill mode. "Blurred background" and "Black bars" keep the whole picture; "Fill (crop edges)" cuts the edges; "Stretch" distorts it.
Why did my width change slightly?
Encoders need even dimensions, so odd sizes are rounded to the nearest even number.
Related video tools
- Video ResizerScale a video down to 1080p, 720p, 480p or 360p and keep the proportions.
- Video Aspect Ratio ConverterTurn a horizontal video into vertical or square, or the other way around.
- Video CropperDrag the crop box, pull a corner, or pick a ratio such as 1:1 for Instagram or 9:16 for TikTok.
- Resize Video to 720pScale a video to 720p (HD) and keep its proportions.
- TikTok Video ResizerFit a video to TikTok's recommended sizes.
- Video CompressorShrink any video to a fraction of its size while keeping it sharp, or type the exact size you need in MB.
- Resize Video by PercentageShrink or enlarge a video by a percentage of its current size.
More in resize video (20 tools), or browse all video tools..