Resize a video
Change a video’s resolution, from 4K down to 240p or to a width and height you choose. Resized on this device, never uploaded.
- Nothing is uploaded
- Works offline after first visit
- Open source
- No watermark · limit is your device’s memory; phones hold less
Resizes a video, for example 4K to 1080p or 1080p to 720p, from MP4, MOV or WebM to MP4. It is free, needs no account and adds no watermark, and your files are not uploaded: everything runs in your browser on your device. The size limit is your device’s memory, and phones hold less; give the page a short while after one visit to save itself for offline use, and then it works offline.
Done
Open the network tab. Your files never appear in it.
Add files and run the tool to see every request this tab makes.
Your files are processed on this device and never sent to a server. Reload the page to clear everything from memory.
How it works
- Drop one or more videos (MP4, MOV, WebM or MKV), or tap to pick them.
- Choose a new size: 1080p, 720p and so on, a percentage, or a custom width and height.
- Resize. Each video is re-encoded at the new size into an MP4 and downloads straight away.
In your browser, not on a server
Mediabunny (MPL-2.0) reads the MP4, MOV, WebM or MKV container in your tab. Your browser’s own video decoder and encoder (WebCodecs) decode each frame, scale it to the new size and encode it again, H.264 where the browser has it and VP9 or AV1 otherwise. The sound is copied as it is when the MP4 can hold it, and Mediabunny writes the new MP4 in memory.
Compared with upload-based tools: Online resizers upload the whole video before they start, which for a 4K phone clip can take longer than the resize, cap free files at a few hundred megabytes, and often add a watermark. Here the video never leaves your device.
Verify it yourself. Give the page a short while after one visit to save itself for offline use, then turn off Wi-Fi or switch to airplane mode and run the tool again. Or open your browser's developer tools (F12, or Cmd-Option-I on a Mac), pick the Network tab, and watch it while you convert. The panel above does the same count for you.
Questions
Is my video uploaded?
No. Your browser decodes and re-encodes the video with its own video encoder, in this tab. There is no server in the process, so there is no upload and no watermark.
What does 720p mean for a vertical phone video?
The p number sets the short side. A landscape 1920×1080 video at 720p becomes 1280×720, and a portrait 1080×1920 one becomes 720×1280, so tall videos stay tall.
Will the aspect ratio change?
Not with the preset sizes, which keep the shape of the picture. With a custom size, fill in only the width or only the height to keep the shape; fill in both and the picture is stretched to fit exactly.
Does making a video smaller also make the file smaller?
Usually, because there are fewer pixels to store. To aim for a particular file size, such as 10 MB for Discord, use Compress video instead.
More video and audio tools
Rotate video
Turn a sideways or upside-down video the right way up, or mirror it. Done on this device, never uploaded.
Crop video
Cut away the edges of a video, or crop it to vertical or square for social media. Cropped on this device, never uploaded.
Change video speed
Make a video faster or slower, with sound that stays at the right pitch. Done on this device, never uploaded.
Merge videos
Combine clips into a single video, in the order you choose. Done on this device, never uploaded.
Popular conversions
Guides
- How to resize a videoGetting a video down from 4K to 1080p, or to an exact width and height a platform expects, is a different setting than just compressing it. Here is how, in the browser.
- How to crop a videoCropping cuts away the edges of the picture, which is different from trimming the length. Here is where each device does it, and a private browser option.