Health calculator

Free height comparison calculator

Compare two heights in two seconds. Enter person A and person B in centimetres or feet and inches, and the calculator returns the difference (in cm and ft-in), who's taller, the ratio, and how much taller the taller person is as a percentage — updated live, as you type.

InputsLive
Units
Person A height
cm
Person B height
cm
How the comparison works
Both heights are put into centimetres, then the calculator takes the difference (taller − shorter), the ratio(taller ÷ shorter), and the percentage— how much taller the taller person is, measured against the shorter. It does not matter which person you enter first; the gap and ratio are the same either way, and equal heights simply give a difference of zero.
Result
Height difference
15.0 cm (5.9 in)
Person A is taller — 5 ft 10.9 in vs 5 ft 5.0 in.
TallerPerson A
Difference15.0 cm (5.9 in)
Ratio1.09
Taller by9.1%
The two heights
PersonHeight
Person A5 ft 10.9 in (180 cm)
Person B5 ft 5.0 in (165 cm)

An exact comparison of the two heights you enter. How accurate is it?

Results are estimates. Consult a professional.

Definition

What is a height comparison calculator?

A height comparison calculator takes two heights — person A and person B — and tells you exactly how they relate: the difference between them, which person is taller, and how big the gap is as a ratio and a percentage. Enter two heights in centimetres or feet-and-inches and it returns all of that instantly, in whichever unit you are working in.

It answers the everyday question "how much taller is one person than another?" without the mental arithmetic of converting feet-and-inches to a single number and subtracting. Couples comparing themselves, parents tracking a child against a sibling, and sports fans sizing up two athletes all reach for the same tool — two heights in, the gap and its context out.

The calculator always reports the difference as a positive number and names the taller person for you, so it does not matter which height you type first. Swapping A and B gives the same gap, ratio, and percentage.
Method

How to compare two heights

Comparing two heights is a short, fixed sequence. The only real work is getting both heights into the same unit first — everything after that is one subtraction and two divisions.

  1. Put both heights in the same unit. If one is in feet-and-inches and the other in centimetres, convert. The calculator keeps everything in centimetres internally (1 inch = 2.54 cm), so 5 ft 9 in becomes 175.3 cm.
  2. Find the difference. Subtract the shorter height from the taller: difference = taller − shorter. This is always a positive number, and it is what most people mean by "the height difference."
  3. Find the ratio. Divide the taller height by the shorter: ratio = taller ÷ shorter. A ratio of 1.10 means the taller person is 10% taller.
  4. Find the percentage. Express the gap relative to the shorter person: percentage taller = (taller − shorter) ÷ shorter × 100. The calculator does all four steps live as you type.
difference = taller shorter
ratio = taller ÷ shorter (always ≥ 1)
percent taller = (taller shorter) ÷ shorter × 100
Worked example

A worked example using the height comparison calculator

Example: 5 ft 11 in vs 5 ft 5 in

Alex is 5 ft 11 in (180 cm) and Sam is 5 ft 5 in (165 cm). Here is exactly how the calculator compares them.

Step 1 — Put both heights in one unit

Alex's 5 ft 11 in is 180 cm and Sam's 5 ft 5 in is 165 cm (using 1 inch = 2.54 cm). With both in centimetres, the comparison is just arithmetic.

Step 2 — Subtract to get the difference

180 cm − 165 cm = 15 cm, which is about 5.9 inches. Alex is the taller of the two, so the calculator labels Alex "taller" and reports a 15 cm (≈ 6 in) gap.

Step 3 — Work out the ratio and percentage

The ratio is 180 ÷ 165 = 1.09, and the percentage is (180 − 165) ÷ 165 × 100 = 9.1%. So Alex is about 9% taller than Sam.

Alex is taller by 15 cm (5.9 in) — about 9.1% taller
180 cm vs 165 cm: a 15 cm difference, a ratio of 1.09, and Alex standing about 9% taller than Sam. Swap the two heights and you get the identical gap — only the named "taller" person changes.
Three views of the gap

Difference vs. ratio vs. percentage — three ways to compare heights

The calculator gives you three numbers for the same comparison, and they answer subtly different questions. Knowing which to quote keeps you from over- or under-stating a gap.

  • The difference (e.g. 15 cm / 5.9 in) is the raw gap — the number you would measure with a tape held between the tops of two heads. It is absolute, so a 15 cm gap is 15 cm whether the pair is short or tall.
  • The ratio (e.g. 1.09) tells you how many times one height is of the other. It is handy for scaling — a ratio of 1.09 means one person is 1.09× the other's height, so in a side-by-side drawing the taller bar is 9% longer.
  • The percentage taller (e.g. 9.1%) restates the ratio as "X% taller," measured against the shorter person. It is the most intuitive way to say how much bigger the gap feels proportionally.
A note on "percentage difference." This calculator reports how much taller the taller person is, measured against the shorter one — (taller − shorter) ÷ shorter × 100. Some tools instead divide by the taller height, which gives a slightly smaller number for the same pair (e.g. 8.3% rather than 9.1% for 180 vs 165 cm). Same gap, different denominator — so it is worth checking which one a given site uses.

The same 15 cm gap is proportionally larger for a shorter pair than a taller one. Between 165 cm and 180 cm it is about 9% taller; between 185 cm and 200 cm — also a 15 cm gap — it is only about 8%. That is the whole reason the percentage and the difference can tell slightly different stories about "how big" a gap is.

Reference

Common height-gap examples

It helps to see where a gap sits among the differences people actually compare. The table below runs the model across common pairings, so you can find the one nearest yours and read across to the difference, ratio, and percentage.

Height AHeight BDifferenceRatioA is taller by
5 ft 6 in (168 cm)5 ft 4 in (163 cm)5 cm (2.0 in)1.033.1%
5 ft 8 in (173 cm)5 ft 5 in (165 cm)8 cm (3.1 in)1.054.8%
5 ft 10 in (178 cm)5 ft 5 in (165 cm)13 cm (5.1 in)1.087.9%
5 ft 11 in (180 cm)5 ft 5 in (165 cm)15 cm (5.9 in)1.099.1%
6 ft 0 in (183 cm)5 ft 4 in (163 cm)20 cm (7.9 in)1.1212.3%
6 ft 2 in (188 cm)5 ft 6 in (168 cm)20 cm (7.9 in)1.1211.9%
6 ft 4 in (193 cm)5 ft 7 in (170 cm)23 cm (9.1 in)1.1413.5%

Figures computed from the model (difference = |A − B|, ratio = taller ÷ shorter, percent = (taller − shorter) ÷ shorter × 100). Centimetre values are rounded, so the stated inch and percentage figures follow the exact cm values.

Notice the two 20 cm rows: that gap is 12.3% when the shorter person is 163 cm but only 11.9% when they are 168 cm. The same absolute difference shrinks as a percentage as both people get taller — exactly what the difference-vs-percentage section describes.
Context

Couple and celebrity height differences

By far the most common use of a height difference calculator is comparing two partners — to see how the gap looks in photos, how it stacks up against the average, or just out of curiosity. So it helps to know what a "typical" gap actually is.

There is no fixed standard, but survey data puts the average gap in male-female couples at roughly 12 to 15 cm (5 to 6 inches) worldwide, with the man usually taller. A 15 cm gap — the worked example above — sits right in that typical band rather than being unusually large. Smaller gaps of a few centimetres are common too; the calculator simply reports whatever the two heights give.

PairingHeightsDifferenceTaller by
Average couple (low end)178 cm vs 165 cm13 cm (5.1 in)7.9%
Average couple (high end)180 cm vs 165 cm15 cm (5.9 in)9.1%
Same height170 cm vs 170 cm0 cm (0 in)0%
Large gap193 cm vs 160 cm33 cm (13.0 in)20.6%

Illustrative pairings. "Average couple" uses the commonly cited 5–6 inch gap; the same-height and large-gap rows show the calculator's full range, including the equal-height case.

The same maths drives celebrity and athlete comparisons — pitting two actors, two basketball players, or a character against a real person. Whatever the pair, the calculator reduces it to one difference, one ratio, and one percentage, so the comparison is the same whether the gap is two centimetres or thirty.

Read with care

How accurate is this height comparison calculator?

The arithmetic is exact — a subtraction and two divisions have no error. The only things that introduce any imprecision are the heights you feed in and the unit rounding, so a couple of points are worth knowing.

  • It is only as accurate as your inputs. Self-reported heights are often rounded to the nearest inch, and people tend to round up. A true gap can differ by a centimetre or two from one computed off rounded heights.
  • Feet-and-inches rounding. The calculator converts ft-in to centimetres with 1 inch = 2.54 cm. Displaying a centimetre result back as ft-in rounds to the nearest tenth of an inch, so a converted value can sit a hair off the exact figure.
  • The percentage depends on direction. "Percent taller" is measured against the shorter person; a "percent shorter" against the taller person would be a slightly different number for the same pair. The calculator always reports how much taller the taller person is.
  • It compares standing height only. It says nothing about why two people differ — build, posture, or footwear can all change how a gap looks in person versus on paper.
Treat the result as an exact comparison of the two numbers you entered. For the gap to match real life, measure both people the same way — barefoot, standing straight, ideally with the same tape.
Methodology

Methodology and sources

The comparison is pure arithmetic: the difference is the absolute value of A minus B, the ratio is the taller height divided by the shorter, and the percentage is the gap divided by the shorter height, times 100. Feet-and-inches convert with the exact factor 1 inch = 2.54 cm. The average-couple context figures come from published survey data on partner height gaps; the average US adult heights used to anchor the example pairings (men ≈ 175 cm, women ≈ 161 cm) are NHANES-style CDC figures.

Average adult height by sex (used to anchor example pairings): CDC / National Health and Nutrition Examination Survey (NHANES), Anthropometric Reference Data.International average heights and the spread between populations: NCD Risk Factor Collaboration (NCD-RisC).
Questions

Frequently asked questions about the free height comparison calculator

A height comparison calculator is a free online tool that helps you compare two heights side by side — see the difference in cm and feet-inches, who's taller, the ratio, and how much taller as a percentage. Two heights are put into the same unit, then compared: the difference is taller − shorter, the ratio is taller ÷ shorter, and the percentage is how much taller the taller person is, measured against the shorter. It runs entirely in your browser with instant results and no sign-up.
Subtract the shorter person's height from the taller person's height: Height Difference = Taller Height − Shorter Height. The calculator does this for you and always returns a positive number, so it doesn't matter which height you enter first.
There is no fixed standard. Survey data places the average gap in male-female couples at around 12 to 15 cm (5 to 6 inches) globally, with the man usually taller — so a 15 cm gap sits right in the typical range rather than being unusually large.
Yes. This calculator outputs both the absolute gap and a percentage. It reports how much taller the taller person is, measured against the shorter person: (taller − shorter) ÷ shorter × 100. Some tools instead divide by the taller height, which gives a slightly smaller number for the same pair.
Centimetres or feet and inches. You can enter both heights in either unit, and the calculator converts internally (1 inch = 2.54 cm) before comparing, so the difference, ratio, and percentage are the same whichever unit you start in.
No. Swapping person A and person B gives the identical difference, ratio, and percentage — only the named taller person changes. The difference is always reported as a positive number.
The ratio is the taller height divided by the shorter height, so it is always 1 or more. A ratio of 1.09 means the taller person is 1.09 times the shorter person's height — i.e. about 9% taller. Equal heights give a ratio of exactly 1.
About

About this height comparison calculator

This height comparison calculator runs entirely in your browser — the heights you enter never leave your device. It converts both heights to centimetres, then reports the difference, ratio, and percentage, updating instantly as you type.

Calculators Cloud offers 400+ free tools with no sign-up. If you want to know how a single height ranks rather than compare two, try the height percentile calculator; the Health calculators shelf also has BMI and ideal weight tools. Or browse the full calculator directory.

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