# How big is the height difference?

Compares two heights in feet and inches or centimetres: the height difference, who is taller, and how many percent taller or shorter, drawn side by side.

- Page: https://www.acalculator.org/everyday-life/height-comparison-calculator
- JSON spec: https://www.acalculator.org/everyday-life/height-comparison-calculator.json
- Version: d374bc3eff1e

## Default answer

Example with the default inputs (Height of person A 5 ft 10 in, Height of person B 5 ft 4 in): The height difference between 5 ft 10 in and 5 ft 4 in is 6 in (15.2 cm); Person A is taller.

## Inputs

| Key | Label | Description |
| --- | --- | --- |
| a | Height of person A | The first height, without shoes. |
| b | Height of person B | The second height, without shoes. |

## Outputs

| Key | Label | Description |
| --- | --- | --- |
| difference | Height difference | The taller height minus the shorter one. |
| differenceCm | Difference in centimetres | The same difference in centimetres. |
| taller | Who is taller | Which of the two heights is greater. |
| percentTaller | Taller one is taller by | The difference as a percent of the shorter height: (taller − shorter) ÷ shorter × 100. |
| percentShorter | Shorter one is shorter by | The difference as a percent of the taller height: (taller − shorter) ÷ taller × 100. |
| ratio | A ÷ B | Height A divided by height B. |

## Method

Difference = taller − shorter. Percent taller = difference ÷ shorter × 100. Percent shorter = difference ÷ taller × 100. Ratio = A ÷ B.

## Assumptions

- Each height is from 1 cm to 3 m (about 0.39 in to 9 ft 10.1 in), typed in feet and inches, inches, centimetres or metres.
- Units convert exactly: 1 in = 2.54 cm, 1 ft = 12 in.

## Worked examples

1. a = 1.778, b = 1.6256 gives difference = 0.1524, taller = Person A is taller, percentTaller = 9.375%, percentShorter = 8.571429%, ratio = 1.09375. Source: NIST SP 811 (2008), Appendix B: 1 in = 2.54 cm exactly, https://www.nist.gov/pml/special-publication-811.
2. a = 1.6, b = 1.85 gives difference = 0.25, taller = Person B is taller, percentTaller = 15.625%, percentShorter = 13.513514%, ratio = 0.864865. Source: NIST SP 811 (2008), Appendix B: 1 in = 2.54 cm exactly, https://www.nist.gov/pml/special-publication-811.
3. a = 1.8288, b = 1.8288 gives difference = 0, taller = Both are the same height, percentTaller = 0%, ratio = 1. Source: NIST SP 811 (2008), Appendix B: 1 in = 2.54 cm exactly, https://www.nist.gov/pml/special-publication-811.

## FAQ

### How do I work out the height difference between two people?

Put both heights in the same unit and subtract the shorter from the taller. 5 ft 10 in is 70 in and 5 ft 4 in is 64 in, so the difference is 70 − 64 = 6 in (15.24 cm).

### How many percent taller is one person than another?

Divide the difference by the shorter height and multiply by 100. 70 in against 64 in: 6 ÷ 64 × 100 = 9.375%, so the taller person is about 9.4% taller.

### Why are "percent taller" and "percent shorter" different numbers?

Each one divides the same difference by a different height. "Taller by" divides by the shorter height, "shorter by" divides by the taller one. For 70 in and 64 in that is 9.375% and 8.571%.

### How do I compare a height in feet with one in centimetres?

Type each height in its own unit; the calculator converts both. One inch is exactly 2.54 cm, so 6 ft (72 in) is 182.88 cm, and 6 ft against 182.88 cm is no difference at all.

### Is a 6 inch height difference a lot?

It depends on the heights. 6 in is 15.24 cm, about 9% of a 5 ft 4 in person. The chart draws both heights to scale, so you can see the gap.

### Should I measure with shoes on?

Measure both people the same way. Shoes can add 1 in (2.5 cm) or more, so for a fair comparison measure both without shoes, standing straight against a wall.

## Sources

- NIST Special Publication 811 (2008), Guide for the Use of the International System of Units, Appendix B: 1 in = 2.54 cm exactly, 1 ft = 12 in. Retrieved 2026-10-02. https://www.nist.gov/pml/special-publication-811