A video that is the wrong size is a small problem that stops a lot of posts. It has black bars on a phone, it is cropped in a feed, or an upload form simply refuses it. The fix is to resize video to the exact width and height the place you are posting wants.
This video resizer does that in your browser. You pick one of five ready-made sizes or type your own, choose how the picture should fill the new shape, and press Resize. Your file is never uploaded, so it is quick to try and private by design.
Below you will find what each setting does, which size suits which job, and the small details that decide whether the result looks right.
How to resize a video, step by step
The video resizer changes the width and height of a clip, and its shape if you want, in one pass. You need no account, and nothing is added to the picture.
- Drop your video onto the page, or choose it from your device. You can add several files and resize them all with the same settings.
- Under Size, tap a tile: 9:16 vertical, 1:1 square, 4:5 portrait, 16:9 Full HD, 16:9 HD, or Custom.
- Under "When the shape is different", choose Fill, Fit or Stretch. This decides what happens when your video is not the same shape as the size you picked.
- Check the From and To lines. From is your original size and To is what you will get.
- Press Resize. When it finishes, save each result, or download them all as a zip.
The preview on the stage changes shape as you choose, so you can see the new frame and the fit before you commit. If you only need to cut away part of the picture rather than change its size, use crop video instead.
Pick the right size for where the video is going
There is no single best size. The right one depends on where people will watch. These are the five sizes on the Size tiles, with the job each one usually suits.
| Tile | Output size | Good for |
|---|---|---|
| 9:16 vertical | 1080×1920 | TikTok, Reels, Shorts |
| 1:1 square | 1080×1080 | Instagram feed |
| 4:5 portrait | 1080×1350 | Instagram portrait |
| 16:9 Full HD | 1920×1080 | YouTube |
| 16:9 HD | 1280×720 | 720p, X / Twitter |
If you already know the platform, there are shortcut pages that open with the right tile selected: resize video for TikTok (which also suits YouTube Shorts), for Instagram and for YouTube. They use this same tool.
Tall, square or wide
Think about the shape first and the number second. A tall 9:16 frame fills a phone held upright. A 1:1 square sits evenly in a feed. A 4:5 portrait is a little taller than a square and takes up more of the screen. A wide 16:9 frame fits a laptop, a television or a YouTube player.
If your clip was filmed sideways and you want it tall, you will usually combine a size change with a fit choice. That is the next section.
Change video resolution: Full HD, HD or your own
Both tiles are 16:9. Full HD is 1920×1080 and HD is 1280×720, the size for places that only show video at 720p. To change video resolution to anything else, choose Custom and type an even width and height from 16 to 7,680. Resizing a small video up to a bigger size makes the frame larger but cannot add detail that was never filmed.
Change the aspect ratio of a video: Fill, Fit or Stretch
Changing a video's aspect ratio means picking a tile of another shape and deciding how the picture meets it. Say you have a wide 16:9 clip and you pick the 9:16 vertical tile. Something has to give. The three tiles under "When the shape is different" let you choose what.
| Choice | What it does | Use it when |
|---|---|---|
| Fill | No bars. Edges are cropped | You want the whole frame covered and can lose a little at the sides |
| Fit | All of it, with bars | You must keep every part of the picture |
| Stretch | Distorts the picture | You really do want the picture pulled to the new shape |
Fill is the default. It scales the picture until it covers the frame, then trims whatever hangs over. People in the middle of the shot stay in view, but things at the edges can be cut off.
Fit does the opposite. It scales the picture down until all of it is visible and adds bars to fill the rest. Nothing is lost, but you get empty bands above and below, or at the sides.
Stretch squeezes or pulls the picture to the new shape. Circles turn into ovals and faces look wrong, so use it sparingly. It is there for the rare case where distortion is what you want.
Custom size: type your own width and height
If none of the five tiles is right, choose Custom. Two fields appear, Width and Height, along with a switch called Keep the proportions.
- Numbers must be whole and even, from 16 to 7,680. If you type an odd number, it is rounded to the nearest even one.
- With Keep the proportions on, change one side and the other follows, using the shape of your original video. Type a width of 1280 on a 16:9 clip and the height becomes 720.
- Switch Keep the proportions off to set both sides freely. Then use Fill, Fit or Stretch to decide how the picture meets the new shape.
Even numbers are needed because the video is saved as an MP4, and that format works with whole, even pixel sizes. The To line shows the exact size you will get, so there is no guessing.
A custom size is handy when a form asks for something specific, such as a banner, an email header or a screen at an unusual shape. It is also a simple way to shrink the picture when you want to change video dimensions before sharing. If your goal is a smaller file rather than a smaller picture, try the compress video tool, which is built for that.
Resize video privately, without uploading
This video resizer runs on your own computer, inside the browser tab. The video never leaves your device, and the server does no video work at all.
- Free to use, with no account and no watermark on the result.
- Video tools are not counted in the free daily limit, which applies to document conversions only.
- It works in current Chrome, Edge and Firefox.
- Most videos have no size limit. Some files, such as certain AVI or WMV videos, take longer and can be up to 2 GB.
The result is saved as an MP4, and the file name ends with the new size, for example _1080x1920. Resizing never turns or mirrors the picture. If writing in a selfie clip reads backwards, flip the video left to right, and if you need the top and the bottom swapped, the upside down video page does that.
Resize your video now
To get a good result from the video resizer, choose the size for where the video is going, then decide whether the picture should Fill, Fit or Stretch to match. Fill is the safe default, Fit keeps everything, and Custom covers any other size from 16 to 7,680 pixels.
Everything happens in your browser, so nothing is uploaded and nothing is watermarked. Drop your video in the tool above, pick a size and press Resize.
