Skip to content
New: Mastershot Screen Recorder for Chrome. Record your screen and webcam to MP4, free, with no watermark.Add to Chrome It's free

Change aspect ratio

Turn a video vertical (9:16, 1080 × 1920 for YouTube Shorts, TikTok, and Reels), square, or widescreen without cutting anything off, or crop it to fill the new shape. It's free, and the video stays on your device.

Files stay on your device

Drop a video to reshape

Choose 9:16, 1:1, 4:5, or 16:9, then keep the whole picture on a blurred background or crop to fill.

MP4, MOV, MKV, WebM, MPEG-TS, and 3GP videos.

How to change a video’s aspect ratio

Pick 9:16 for Shorts, Reels, and TikTok, 1:1 or 4:5 for the Instagram feed, or 16:9 for YouTube. Keep the whole picture on a blurred or black background, or crop it to fill the frame. This aspect ratio converter runs in your browser, so the video is never uploaded.

  1. Step 1

    Choose a video
    Pick the video you want in a new shape.

  2. Step 2

    Choose the shape
    Pick 9:16, 1:1, 4:5, or 16:9, then bars or a crop.

  3. Step 3

    Download the video
    Export it at the new aspect ratio.

What to expect

Supported inputs
MP4, MOV, MKV, WebM, MPEG-TS (.ts, .mts), and 3GP videos. AVI, WMV, and FLV files can’t be opened yet.
What happens
The video is re-encoded in its source format at the new shape. With bars, the frame keeps the source’s short side, so a 1080p video becomes 1080 × 1920 for 9:16. With a crop, the chosen area is kept at its own resolution.
Limits
A video track is required, and subtitle tracks are left out. Frames are kept within 3840 × 2160, which browser encoders handle.

For one format, size, or task

The same tool, with the settings already picked.

Also

Your files stay on your device

Your computer does the work, so the file never has to be uploaded, and that’s also why it’s free: there’s no server time for us to pay for. You don’t need an account, and nothing you make gets a watermark.

“Thanks a ton, man. Your tool was perfect for what I needed.”
Mr. Cerulean, a supporter

Questions

9:16, vertical, at 1080 × 1920 pixels fills a phone screen. YouTube counts any square or vertical video up to three minutes long as a Short; a landscape one stays a regular video. Choose 9:16 to turn it into a Short without losing its edges.

9:16. A 3:4 video also counts as a Short, but it shows with empty space above and below on a phone; 9:16 fills the screen.

Reels and Stories are 9:16 (1080 × 1920). Feed posts can be square, 1:1 (1080 × 1080), or portrait, 4:5 (1080 × 1350), which takes up the most room in the feed.

Choose 16:9. Bars keeps the whole picture in the middle with a blurred or black background on the sides; Crop keeps a 16:9 slice of the frame, which you can drag into place.

Bars keeps everything in the shot and is right for text, faces near the edges, and screen recordings. Crop fills the screen but cuts off the sides, so it suits a subject that stays near the middle.

Related tools