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Resize

Resize a video to 1080p, 720p or 480p online

Scale a video down to a smaller resolution and get a much smaller file — 4K phone footage to 1080p, a screen recording to 720p for a chat upload. The aspect ratio is kept, nothing is ever upscaled, and the whole job runs in this tab without uploading anything.

Drop your video here

or click to browse — MP4, MKV, MOV, WebM, AVI and more

How to downscale a video in your browser

  1. 01

    Open the file

    Drag an MP4, MOV, MKV, WebM or AVI onto the drop zone above, or click it and pick the file. The resolution of the source is what you are about to cap.

  2. 02

    Pick a Max resolution

    The control below the timeline offers Original, 1080p, 720p and 480p. This page starts at 720p; choose 1080p for 4K footage you want to keep sharp, or 480p for very long clips and slow connections.

  3. 03

    Optionally cut, speed up or mute

    Anything else on the timeline is applied in the same pass. Trimming the clip and resizing it together is the usual way to get a large recording down to size.

  4. 04

    Press the button

    With no edits queued the apply button reads "Convert video"; with edits it reads "Apply All Edits". The first run downloads the ~32 MB engine, which is cached afterwards.

  5. 05

    Compare and download

    The finished file appears with its size next to it. If it is still too big, go a tier lower or trim more; the encode is quick to repeat because the engine is already loaded.

What the Max resolution control does

It caps the height of the output. Pick 720p and a 3840×2160 source comes out at 1280×720; a 1080×1920 vertical phone clip comes out 720 pixels tall and about 405 wide, nudged to an even number for a reason below. The width is never something you set; it follows from the source's proportions, so the picture is never stretched or squashed.

Under the hood this is one FFmpeg filter, scale, called as scale=-2:min(ih,720). The min(ih,720) takes whichever is smaller, the source's own height or the cap. The -2 means "work out the width from the aspect ratio, rounded to an even number", because H.264 with the usual 4:2:0 chroma layout needs even dimensions. That is why an odd computed width gets nudged by a pixel.

It only scales down. The filter is always inserted when a cap is chosen, but because the height is the smaller of the cap and the source's own height, a source already at or below the cap passes through at its original size: a 720p video with the cap at 1080p stays 720p. Upscaling adds pixels without adding detail, so it is deliberately not on offer.

Because the cap is decided inside FFmpeg from the decoded frames, it does not depend on the browser being able to preview the file. An MKV or an AVI that shows no preview is downscaled just the same.

Which tier to pick

1080p

Sharing 4K phone or drone footage. Phones record 4K by default now, and almost nobody watches it that way. 1080p is a quarter of the pixels, still crisp on any screen, and encodes noticeably faster.

720p

Email, chat and upload limits. The tier for a screen recording heading to a support ticket, a clip going into a group chat, or anything with a hard size cap. Text on a screen recording is still readable; the file drops sharply.

480p

Very long clips and slow connections. A lecture, a whole meeting, a multi-hour capture — or anything that has to go over a poor mobile link. Fine detail goes, but speech, slides and faces survive.

What to expect from the file size

Halving the height quarters the number of pixels, and the encoder's bit budget follows the pixel count closely, so each tier down is a large step: 4K to 1080p is roughly a quarter of the pixels, 1080p to 720p a bit under half, 720p to 480p a bit under half again. Exact output sizes depend entirely on the footage — a static screen recording compresses far better than a handheld shot of trees in the wind — so the honest advice is to read the size shown next to the download link rather than to predict it.

Two things push the other way. The video is re-encoded with libx264 at the ultrafast preset and CRF 28, and ultrafast spends bits to save CPU time. And a variable-frame-rate screen recording comes out with regular timing, which can cost size on a mostly static capture. Neither usually outweighs a resolution drop, but it is why a 1080p cap on a 1080p source can produce a larger file — the cap changes nothing at that size and only the re-encode happens. The formats page has the encoder details.

Resolution is not compression

Worth stating plainly, because the two get conflated. This page makes the picture smaller, which makes the file smaller as a side effect. Compression makes the file smaller at the same resolution, by lowering the bitrate and letting the encoder work harder. If you want a 1080p video to stay 1080p and just take up less space, that is the second job, and it is what the sibling tool smaller.video is built for — same in-browser FFmpeg, different control.

The two combine well: downscale here first if the resolution is genuinely more than you need, then compress the result if it still has to be smaller.

What this does not do

There is no custom width or height, no crop, no rotate, no padding and no aspect-ratio change. It cannot turn a landscape recording into a vertical 9:16 post or letterbox a 4:3 clip into 16:9. It does not upscale. It is one control with three settings, and that is deliberate: it covers the cases where a resolution cap is the right answer without pretending to be a reframing tool. For the platform-limit workflow — getting a clip under a duration ceiling, which often comes up alongside size — trimming a video to a specific length covers that.

Questions about resizing video

Can I set a custom width and height?
No. The control is a cap on the height — 1080p, 720p or 480p — and the width follows from the source aspect ratio. There is no free-form width and height field, no crop and no aspect-ratio change. If you need a specific frame size or a 9:16 reframe, that is a different tool.
Will resizing make my video larger or higher resolution?
No. The cap only ever scales down. A 720p video with the cap set to 1080p is left at 720p; upscaling adds pixels but no detail, so it is deliberately not offered.
Does resizing keep the aspect ratio?
Yes. FFmpeg is run with scale=-2:min(ih,H), which sets the height to the cap (or to the source's own height if that is smaller) and computes a width that preserves the original proportions, rounded to an even number so the encoder accepts it. A 16:9 clip stays 16:9, a vertical phone clip stays vertical.
Is resizing the same as compressing?
No. Resizing reduces the number of pixels, which reduces the file size as a side effect. Compressing keeps the resolution and lowers the bitrate. This page does the first; for the second at the same resolution, the sibling tool at smaller.video does that.
Is the video uploaded to resize it?
No. The scale filter and the re-encode both run inside your browser tab with FFmpeg WebAssembly. Nothing is transmitted, and the page's cookie-less analytics see a page view and never the file.

Other edits in the same pass

The cap sits alongside everything else on the timeline: cut a section out, speed a section up, remove the audio or change the container, all in one encode. None of it is uploaded — here is what does and does not leave your device, and here is how it works.

Guides related to this

Working with very large files in a browser tab, what a re-encode costs, and what an online editor actually does with your file.

All video editing guides