New height = original height × target width / original width; a target height works the other way round.
Simplify dimensions and calculate a proportional resize to a target width or a target height, with one-click presets for 16:9, 4:3, 1:1, 21:9 and 9:16.
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Simplify dimensions and calculate a proportional resize to a target width or a target height, with one-click presets for 16:9, 4:3, 1:1, 21:9 and 9:16.
1920 × 1080 simplifies to 16:9. At width 1280 the proportional height is 720 — and a target height works too: 1080 tall at 16:9 needs a width of 1920. The preset chips load 16:9, 4:3, 1:1, 21:9 and 9:16 dimensions in one click.
New height = original height × target width / original width; a target height works the other way round.
It is a visual aid, not a replacement for the numeric output. Some charts compare values with different units, and those magnitudes are not directly comparable.
Check units, signs, assumptions and rounding first. The tool cannot know whether the values you enter describe the real situation correctly.
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