Resize video

Change a video's resolution to 1080p, 720p or a size of your own. Proportions are kept, and nothing is uploaded anywhere.

Drop your files here

.mp4, .mov, .mkv, .webm, .avi · up to 200 MB

Choose files

How to Resize the video

1
Add your video
MP4, MOV, MKV, WebM or AVI, up to 200 MB and five minutes. Phone footage in 4K is the usual thing to bring down to 1080 or 720.
2
Pick a resolution
The presets are named by the short side, the way people say them: 720p means 720 pixels tall on a landscape clip and 720 wide on a vertical one.
3
Press Build video, then download
Nothing is encoded before you press it. The result is an MP4 at the new size, with the same length and the sound kept, and the player shows it before you download.

Resolution is the biggest lever on file size

Bytes follow pixels. Going from 1080p to 720p throws away more than half the picture data before compression even begins, which is why resizing usually beats compressing when a file has to get dramatically smaller. The bitrate is scaled along with the frame: a video that was well encoded at 1080p gets proportionally fewer bits at 720p, so the result looks about as good as the original did, just smaller. Sending it at 1080p and letting the recipient's phone shrink it to a 6-inch screen wastes the difference; resizing first keeps only what will be seen.

Proportions are never broken

Picking a preset scales both sides by the same factor, so nothing is stretched. If you type your own width with the aspect lock on, the height is worked out for you. Turning the lock off lets you set both sides independently, and then the fit setting decides what happens to the mismatch: contain fits the whole frame inside and leaves bars, cover fills the frame and loses the edges, stretch squeezes the picture to fit. Stretch exists because people occasionally need it, not because it is a good idea. Distorted faces read as a mistake to anyone watching.

Why sides are rounded to even numbers

H.264 stores colour at half resolution horizontally and vertically, so both sides have to be divisible by two. An odd number is not a rounding annoyance to the encoder, it is a configuration it will refuse outright. Rather than fail, the tool rounds down by one pixel, which is invisible. The same rule is why a target like 1080 × 607.5 comes out as 1080 × 608.

Making a video bigger

Clicking a preset bigger than the source enlarges the video: the click switches off “Never enlarge”, and a line under the settings says the picture is only stretched. A size that is already selected when the page opens, such as the 1080p this page starts with or the 720p of the 720p page, is not a click: a smaller clip stays as it is, and the page says so, until you click a size or switch off “Never enlarge” under “More settings”. What enlarging cannot do is invent detail: a 720p clip blown up to 1080p is the same picture made of more pixels, and the file grows with the pixel count, about 2.25 times, for nothing. If you only need a 1080p canvas because a platform demands one, the aspect ratio tool is the better way there: it fills the extra space deliberately instead of pretending there was detail to begin with.

Scaled on your device

Decoding, scaling to the size you picked and encoding again all run on your own device, with the encoder built into your browser, and a clip smaller than the target is not blown up unless you allow it. No frame is uploaded, there is no account or queue, and you can resize as many videos as you need.

Frequently asked questions

Will resizing lose quality?

Making a video smaller discards detail by definition, but the bitrate is scaled to match, so the result looks about as good at its new size as the original did at its old one. What you lose is only visible if you then blow the video back up.

Can I make a video higher resolution?

Yes, by clicking a preset bigger than the source: the click switches off “Never enlarge”. A size that is already selected when the page opens does not, so a 640 × 360 clip on the 720p page stays as it is until you click 720p or switch that off under “More settings”. Enlarging still cannot add detail: the same picture is made of more pixels, and the file grows with the pixel count. If a platform demands a bigger canvas, the aspect ratio tool is usually the better answer.

Why did my numbers change by a pixel?

H.264 requires both sides to be even, so an odd number is rounded down by one. This is a hard requirement of the format, not a preference.

What does 720p mean for a vertical video?

720 pixels across. The presets measure the short side, which is how the words are used in practice: a vertical 720p clip is 720 × 1280, not 1280 × 720.

Is the sound kept?

Yes. The soundtrack is encoded again as AAC, aiming at the bitrate the source had, up to 320 kbps. Where the browser has no AAC encoder of its own, the page loads one; only if that fails is the sound saved as Opus, which plays in Chrome, Firefox and Edge but not in QuickTime.

Which browsers does this work in?

Chrome 94 and later, Safari 26 and later, and desktop Firefox 130 and later, which have the H.264 encoder this needs. On browsers without it, the page says so up front rather than failing halfway through.

Why is there a 200 MB limit?

Because frames are decoded and encoded in your browser's memory. Past that size, browsers start running out of room. For a bigger file, trim it first and resize the part you need.