Length Converter
Convert between millimetres, centimetres, metres, kilometres, inches, feet, yards, miles and nautical miles using exact conversion factors.
Your details
Result
Result
- Conversion rate
- 1 cm = 0.393701 in
Common conversions from this unit
| Unit | 1 cm equals |
|---|---|
| Millimetres (mm) | 10 mm |
| Metres (m) | 0.01 m |
| Kilometres (km) | 0.00001 km |
| Inches (in) | 0.393701 in |
| Feet (ft) | 0.032808 ft |
| Yards (yd) | 0.010936 yd |
| Miles (mi) | 0.000006 mi |
| Nautical miles (nmi) | 0.000005 nmi |
The formula
result = value × (factor_from ÷ factor_to)Each unit is defined by how many metres it represents. Converting means scaling the input up to metres, then back down into the target unit. Because the inch is defined as exactly 25.4 mm, every metric-imperial conversion here is exact rather than approximate.
Frequently asked questions
How many centimetres are in an inch?
Exactly 2.54. This is a definition, not a measurement — the international yard and pound agreement of 1959 fixed the inch at exactly 25.4 millimetres, so the conversion carries no rounding error.
Why is a nautical mile different from a mile?
A nautical mile is 1,852 metres and was originally defined as one minute of latitude along a meridian, which makes it natural for navigation. A statute mile is 1,609.344 metres and comes from Roman and English land measurement. A nautical mile is about 15% longer.
Related calculators
Mortgage Payment
Work out your monthly mortgage payment including taxes, insurance and PMI, then see exactly how much interest you will pay over the life of the loan.
Compound Interest
See what your savings grow into once interest starts earning interest, with regular contributions and any compounding frequency.
BMI
Work out your body mass index in metric or imperial units, see which WHO category it falls in, and find the weight range that would put you in the healthy band.
Percentage
Answer all four of the common percentage questions — what is X% of Y, X is what percent of Y, percentage increase or decrease, and the original value before a change.
Date Difference
Count the days, weeks, months and years between two dates, including an exact working-day count that skips weekends.
Profit Margin
Turn cost and revenue into gross margin, markup and profit per unit — and work backwards from a target margin to the price you need to charge.