Video Resolution Changer
Rescale any video to 1080p, 720p, 480p or a custom size — pick how the aspect ratio is handled and export a new clip, entirely in your browser.
Drag & drop a video here, or click to browse
No uploads. Your files stay on your device.
How it works
Drop in an MP4, WebM, MOV or any other clip your browser can play, choose a target resolution — 4K, 1440p, 1080p, 720p, 480p, 360p, 240p or your own width and height — and press Change resolution. Every frame is redrawn at the new size on a hidden canvas and re-recorded with the browser's built-in MediaRecorder, giving you a WebM file (VP9 or VP8 video with Opus audio). The video is read straight from disk with the File API, so nothing is uploaded, there is no file-size cap set by a server and no watermark is added.
Four aspect-ratio modes decide what happens when the source shape does not match the target: "Keep aspect ratio" fits the frame inside the target box and outputs the exact scaled size with no bars, "Letterbox" keeps the shape but pads to the exact resolution, "Crop to fill" zooms in and trims the overflow, and "Stretch" distorts to the exact size. The output size, aspect ratio and estimated file size update the moment you change a setting. Because the encoder runs in real time, a two-minute clip takes about two minutes; downscaling is fast and lossless-looking, while upscaling only enlarges pixels and cannot add detail that was never recorded.
Frequently asked questions
How do I change a video's resolution without installing software?
Drop your MP4, WebM or MOV file onto the box above, choose a target resolution — 4K, 1440p, 1080p, 720p, 480p, 360p, 240p or your own width and height — and press Change resolution. The clip is redrawn at the new size on a canvas and re-recorded with the encoder that is already built into your browser, so there is nothing to install and nothing to sign up for. The file never leaves your device: it is read straight from disk with the File API and processed inside this page.
What happens if my video's aspect ratio doesn't match the target size?
You choose. "Keep aspect ratio" fits the frame inside the target box and outputs the exact scaled size with no black bars — a 4:3 clip sent to 1280 × 720 comes out as 960 × 720. "Letterbox to exact size" keeps the shape but pads to the full requested resolution, "Crop to fill" zooms in and trims the overflow, and "Stretch" distorts the picture to hit the exact numbers. The output line updates instantly so you see the real pixel size before you encode.
Why is the result a WebM file, and can I upscale to a higher resolution?
The re-encode uses MediaRecorder, the browser's own encoder, which writes WebM (VP9 or VP8 video with Opus audio) — that is the format every modern browser, player and editor can read without a plugin. Upscaling is allowed, but enlarging only stretches the pixels that were recorded: a 480p source set to 1080p gets bigger and softer, not sharper. Downscaling is where the real win is, cutting file size dramatically with almost no visible loss.