Video Aspect Ratio Converter — 16:9, 9:16, 1:1, 4:5 Online Free

Switch your video between landscape, vertical, square, and story aspect ratios with smart crop or letterbox padding. Free, no watermark, entirely in your browser.

Smart crop or paddingFiles never uploadedNo watermark added

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How to Change Aspect Ratio

Upload your video

Drop any MP4, MOV, or WebM file into the tool, or click to browse.

Pick a target ratio

Choose 16:9 (landscape), 9:16 (vertical for Reels/TikTok), 1:1 (square) or 4:5 (Instagram feed), then pick Crop or Pad mode.

Render and download

The tool re-encodes the file with the new frame, then offers a direct download.

Frequently Asked Questions

What's the difference between Crop and Pad modes?

Crop fills the new frame by cutting away content that doesn't fit. Pad keeps the whole frame visible by adding black bars on the sides or top/bottom.

Which aspect ratios are supported?

16:9 for YouTube and landscape players, 9:16 for TikTok / Reels / Shorts, 1:1 for square posts, and 4:5 for Instagram feed.

Will the quality drop?

The video is re-encoded with CRF 23, which is visually lossless for most content. Cropping does discard pixels, so heavy crops may look softer.

Does it work on mobile browsers?

Yes, but mobile CPUs are slower and RAM is more limited. Shorter clips work best on phones.