How to use the social media video cropper
- Drop a video onto the box or click to choose one.
- Choose the Platform shape: 9:16 (Reels, Shorts, TikTok, Stories), 1:1 (square feed post), 4:5 (Instagram/Facebook portrait feed), 16:9 (YouTube, X, LinkedIn landscape) or 2:3 (Pinterest).
- Under Framing, choose Crop to fill or Pad to fit (bars).
- When cropping, choose which part to Keep: Centre, Left / top or Right / bottom.
- Set Output size: 1080 px on the short side (default), 720 px on the short side, or Keep source sharpness. Press Reframe video and download the MP4.
What it does and when to use it
Most cameras record landscape, while short-video apps and many feeds are built for tall or square posts. Posting the wrong shape means the app crops it for you, often cutting off heads or text, or shows a small video in the middle of the screen. This tool does the reframing and the scaling in one pass, so you decide what stays in shot.
For any other shape, or a rectangle measured in percent, use the general video cropper. If the source is sideways, fix it first with the video rotator. Many apps also limit file size or length, so the video compressor and video trimmer are useful next steps.
How it works
For Crop to fill, the tool takes the largest window of the chosen shape that fits inside the video and slides it to the side you chose to keep. For Pad to fit, it fits the whole video inside a frame of the chosen shape and fills the rest with black. The result is then scaled so its short side is 1,080 or 720 pixels, or left at the crop size for Keep source sharpness.
Every frame is decoded, cropped or padded, scaled and encoded again with Mediabunny and your browser’s WebCodecs encoder in a background worker. Nothing is uploaded.
Worked examples
These sizes come from the tool’s own framing maths, for a 1920×1080 landscape source.
| Shape | Framing | Area used | Output (1080 setting) |
|---|---|---|---|
| 9:16 | Crop, Centre | 608×1080 | 1080×1920 |
| 4:5 | Crop, Centre | 864×1080 | 1080×1350 |
| 1:1 | Crop, Centre | 1080×1080 | 1080×1080 |
| 2:3 | Crop, Centre | 720×1080 | 1080×1620 |
| 1:1 | Pad | whole frame | 1080×1080, bars above and below |
With 720 px on the short side, the 9:16 crop becomes 720×1280.
Limits and tips
- Pad with Keep source sharpness can be huge. A 1920×1080 clip padded to 9:16 at full sharpness is 1920×3414, larger than most apps accept. Use the 1080 setting for padding.
- Long clips take time, particularly on phones, and the output is held in memory until you save it.
- AVI, WMV and FLV are not read here; convert first with the video converter.
Frequently asked questions
Should I crop or pad?
My subject is not in the middle. What can I do?
Why does the 9:16 version look softer than the original?
What format is the result?
How do we know nothing is uploaded? Test it yourself on the privacy proof page.