Feet & Inches to Centimeters

Height is the measurement most often converted by hand — on medical forms, sports profiles, flight bookings — and the one with a built-in trap: feet-and-inches is a mixed unit, and converting it in one step goes wrong more often than not.

The correct method

Convert the mixed measurement to total inches first, then multiply by 2.54:

• 5′10″ → (5 × 12) + 10 = 70 inches
• 70 × 2.54 = 177.8 cm

The classic mistake is treating 5′10″ as the decimal 5.10 feet — that gives 155.4 cm, off by more than 20 cm. Feet-and-inches is base-12, not decimal: 5′10″ is 5.833 feet.

Going the other way

Centimeters to feet and inches reverses the steps:

• 175 cm ÷ 2.54 = 68.9 total inches
• 68.9 ÷ 12 = 5 feet, remainder 8.9 inches → 5′8.9″

Everyday usage rounds to the nearest inch (5′9″), which is why converting a height back and forth can shift it slightly — each system rounds into different buckets.

Why exactly 2.54?

It isn't an approximation. In 1959 the English-speaking countries defined the international inch as exactly 2.54 cm, tying imperial length to the metric system by definition. Every length conversion since is exact arithmetic; only your chosen rounding introduces error.

Common heights at a glance

• 5′0″ = 152.4 cm · 5′4″ = 162.6 cm · 5′8″ = 172.7 cm
• 5′10″ = 177.8 cm · 6′0″ = 182.9 cm · 6′4″ = 193.0 cm

Handy anchors: 6 feet is almost exactly 183 cm, and 170 cm is just under 5′7″.

Where precision matters (and where it doesn't)

Dating profiles survive an inch of rounding; medical dosing, BMI calculations and ergonomic equipment sizing don't. When a form asks for centimeters, convert from your measured height, not from your already-rounded feet-and-inches figure — the double rounding can move you a full centimeter or more.

Skip the arithmetic

The height converter keeps both systems in sync live, shows total inches as a checkable intermediate, and includes a common-heights chart. Computing BMI next? The BMI calculator takes either unit system directly.