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From imperial heights to metric measurements in one step
The US and UK express height in feet and inches; most of the world uses centimeters. This calculator converts any feet-and-inches value to cm using the exact 1959 definition: 1 inch = 2.54 cm, so 1 ft = 30.48 cm.
The formula
cm = (ft × 12 + in) × 2.54
- ft — whole feet.
- in — remaining inches (0–11).
- 2.54 — exact cm per inch (1959 international agreement).
Alternative two-step: convert feet to cm (ft × 30.48) and inches to cm (in × 2.54), then add the results.
Worked example — 5 ft 10 in
Using the default of 5 ft 10 in:
- Total inches: (5 × 12) + 10 = 60 + 10 = 70 in.
- Multiply by 2.54: 70 × 2.54 = 177.8 cm.
So 5′10″ = 177.8 cm exactly.
Conversion table — common heights
| Feet & Inches | CM |
|---|---|
| 4′10″ | 147.32 |
| 5′0″ | 152.40 |
| 5′2″ | 157.48 |
| 5′4″ | 162.56 |
| 5′6″ | 167.64 |
| 5′8″ | 172.72 |
| 5′10″ | 177.80 |
| 6′0″ | 182.88 |
| 6′2″ | 187.96 |
| 6′4″ | 193.04 |
History & standards
The foot has ancient roots — used by Greeks, Romans and medieval Europeans before being standardized nationally. The modern international foot was fixed by the 1959 International Yard and Pound Agreement as exactly 0.3048 m (equivalent: 1 ft = 30.48 cm). The meter is the SI base unit of length, defined since 1983 by the speed of light. Note: NIST retired the US survey foot (which differed by about 2 parts per million) in 2023; the international foot is now the only US legal definition.
Common applications
- Medical records. BMI and clinical records in metric countries require height in cm.
- International travel. Passport height fields outside the US use cm.
- Online shopping. Clothing inseams and sleeve lengths may be listed in inches; many non-US buyers need cm.
- Architecture. US blueprints list heights in ft; metric conversions are needed for international projects.
- Sports. Athletics events report heights in both systems depending on the audience.
Reverse conversion
To convert cm back to feet and inches, divide by 2.54 for total inches, then divide by 12 for feet and take the remainder as inches. Use the cm to feet and inches calculator.
Limitations & gotchas
- Enter whole feet and separate inches. Do not enter “5.10” for 5′10″ — that means 5 feet 10 inches, but decimal notation (5.833… ft) would be different.
- Inches field range. Inches should be 0–11; entering 12 or more bumps you into the next foot.
- Rounding. Results are exact to as many decimals as needed; typical display is 2 d.p.
Sources & references
- NIST SP 811, Guide for the Use of the International System of Units (SI).
- BIPM, The International System of Units (SI), 9th edition.
- 1959 International Yard and Pound Agreement.
- Federal Register Vol. 88, No. 60 (2023) — deprecation of the US survey foot.
FAQs
Convert everything to inches first (feet × 12 + remaining inches), then multiply by 2.54. For example, 5 ft 10 in = (5 × 12 + 10) = 70 in; 70 × 2.54 = 177.8 cm.
5 ft = 5 × 30.48 = 152.4 cm exactly.
6 ft = 6 × 30.48 = 182.88 cm exactly.
Exactly 30.48 cm. This is derived from the 1959 international agreement fixing 1 inch = 2.54 cm and 1 ft = 12 in, so 1 ft = 12 × 2.54 = 30.48 cm.
5′10″ = (5 × 12 + 10) × 2.54 = 70 × 2.54 = 177.8 cm.
The metric system is used in medicine, science and most of the world. Converting to cm is necessary for BMI calculations, medical records, and international clothing sizing where metric measurements are standard.