Resolution Scale Calculator
Scale image width and height by the same percentage while preserving aspect ratio.
How the result changes
Only original width changes; all other inputs stay at your current values. Each dot represents one whole-number input. This is not a forecast of real-world outcomes.
About this calculation
Resolution Scale Calculator: Scale image width and height by the same percentage while preserving aspect ratio. Enter original width, original height, linear scale; the reported quantities are scaled width (pixels), scaled height (pixels), scaled pixel count (pixels). The equations and examples below show how those inputs lead to the result and where the model's assumptions matter.
Formula
new dimension = original dimension × scale / 100, rounded to at least one pixel
Worked example
With Original width: 1920 pixels, Original height: 1080 pixels, Linear scale: 50 %, scaled width is 960 pixels.
Method and inputs
Multiply each original image dimension by the linear scale percentage divided by one hundred. Round each new dimension to an integer pixel because a raster image cannot have a fractional pixel count. Multiply rounded dimensions for total pixels.
Worked example
A 1920 by 1080 image at 50 percent linear scale becomes 960 by 540 pixels, with 518,400 total pixels. The pixel count is one quarter of the original because both dimensions were halved.
Scaling a 1920-by-1080 frame to 150 percent yields 2880 by 1620 pixels, or 4,665,600 pixels. That is 2.25 times the source pixel count. Larger dimensions demand more memory even if an encoder later compresses the stored file.
How to read the result
The scale percentage applies to width and height, not directly to pixel count. In ideal arithmetic, total pixels scale with the square of the linear factor. Rounding can cause a one-pixel aspect-ratio deviation for small sizes.
If only width should change while height is fixed, this proportional scaling calculator is the wrong operation: the image would stretch or crop. Preserve aspect ratio for ordinary resizing, and choose a separate crop or canvas process when a platform requires a different shape.
Assumptions and checks
The calculation changes resolution, not file bytes or visual quality automatically. Encoder settings, color depth and compression determine file size. Upscaling cannot recreate detail absent from the source image. An extreme downscale is capped at one pixel per side.
A 200-percent scale doubles each side and multiplies pixel count by four. Do not expect a 50-percent linear scale to retain half the pixels. Check whether a program interprets scaling as linear dimensions or target pixel area.
Common questions
What does the resolution scale calculator calculate?
It provides integer target dimensions and total output pixels for proportional raster scaling.
When should I recalculate or check another method?
Recalculate if a platform imposes an even-number or macroblock dimension requirement. In those cases round to the allowed dimensions after this geometric calculation and inspect the resulting aspect ratio.
Inputs
- Original width (pixels)
- Original height (pixels)
- Linear scale (%)