Change aspect ratio
Turn a video vertical, square, or widescreen without cutting anything off, or crop it to fill the new shape. Processing stays 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.
Any media file this browser’s engine can read.
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.
Step 1
Choose a videoPick the video you want in a new shape.Step 2
Choose the shapePick 9:16, 1:1, 4:5, or 16:9, then bars or a crop.Step 3
Download the videoExport it at the new aspect ratio.
What to expect
- Supported inputs
- Any media file this browser’s engine can read.
- 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.
Private by design
Your video stays on your device
Mastershot processes your file locally in this browser. It does not need to be uploaded to a server, and you do not need an account to use the tool.
- No upload
- No signup
- No watermark