Aspect ratio resize calculator

The Aspect ratio resize calculator computes aspect ratio resize from the relation new height = new width x (h / w). It takes 3 inputs (original width, original height, new width) and returns the new height. These calculators are for network and systems administrators, software and hardware engineers, and computing students, turning a stated value, address, string or configuration into the exact figure, code or encoding that the rule behind it produces, without working it through by hand. Enter your values below and the result updates instantly, and you can share a permalink that pre-fills the exact calculation. Check the base, unit and width of each input before entering it: hexadecimal against decimal, bits against bytes, binary against decimal prefixes, and 0-based against 1-based positions are the usual sources of a wrong answer here, and a result that is out by a neat factor is far more often one of those than an arithmetic slip. For example, with original width = 4, original height = 3, new width = 8, the new height works out to 6, and the worked example further down the page shows every step so you can follow the arithmetic and reproduce it by hand. This is a standard formula rather than a jurisdiction-specific rule, so it does not depend on an external rate or schedule, and the figure above each result carries the date it was last verified. The result follows the definition and the exact values you supply, so it can differ from what a live system reports: reserved and unusable values, protocol and filesystem overhead, the width and precision of the data type actually in use, and the conventions a particular language, device or display applies all sit outside the calculation, so confirm the figure against the environment it will be used in.

With Original width = 4, Original height = 3, New width = 8, the result is 6.

Formula: new height = new width x (h / w). Source: our documented method, as at 2026-06-22.

New height6

Applies to: any numeric inputs. Method: a standard formula, not a jurisdiction-specific rule. How we document and test our methods, checked 2026-06-22.

The formula

new height = new width x (h / w)

Worked example

With Original width = 4, Original height = 3, New width = 8:

  1. new height = new width x (h / w)
  2. New height = 6

This worked example is one of the automated golden-value tests this calculator must pass before it can publish.

What this assumes

  • Inputs are real numbers in the units shown.
  • The result is the exact value of new height = new width x (h / w); general information, not professional advice.

Frequently asked questions

What formula does this use?

new height = new width x (h / w). This is a standard formula rather than a jurisdiction-specific rule.

Does the result ever change over time?

No. This is a pure formula with no external rate, so the same inputs always give the same result.

Official sources and verification

Reviewed by the CalculatorHub team, edited by James Graham, 2026-06-22. See our methodology. General information, not professional advice.