How many centimetres are in an inch?

Exactly 2.54 centimetres, by definition, which makes one inch 25.4 millimetres. That fixed relationship is what every length conversion between the two systems is built on, so converting cm to inches simply divides by 2.54.

What is a nautical mile?

A nautical mile is 1,852 metres, a little longer than a regular mile of 1,609.344 metres. It is used at sea and in the air because it relates neatly to lines of latitude, with one nautical mile being about one minute of latitude.

How accurate are the conversions?

Each conversion uses the exact, internationally defined factor for the unit, not a rounded approximation, so the maths is precise. The result is shown to several significant figures and rounded only for display. For everyday and most professional use, the figures are exact to well beyond the precision you need.

Does this work offline and is anything sent to a server?

The conversion runs entirely in your browser, so nothing you type is sent anywhere, and once the page has loaded it keeps working with no connection. There is no sign-up and no limit on how many conversions you make.

Length Converter

Convert length and distance between metric and imperial units: metres, kilometres, centimetres and millimetres, plus inches, feet, yards, miles and nautical miles. Type a value and see it in every unit at once, with exact factors. Free and instant.

Exact, standard factors
100% free
No sign-up, no app
Instant as you type
Works offline after first load

Read the guide: How to Convert cm to Inches

Convert

From

3.2808399ft

1 m = 3.2808399 ft

1 m in every unit

Millimetre1,000 mm

Centimetre100 cm

Metre1 m

Kilometre0.001 km

Inch39.370079 in

Foot3.2808399 ft

Yard1.0936133 yd

Mile0.00062137 mi

Nautical mile0.00053996 nmi

How to use it

1
Enter a value

Type the number you want to convert. The result updates as you type, with no button to press.
2
Pick the units

Choose what you are converting from and to. Swap them with one click if you need the reverse.
3
Read or copy

See the exact result, plus a table of your value in every unit. Copy any line you need.

When it comes in handy

DIY and measuring

Switch a measurement between centimetres and inches, or metres and feet, when a tool or plan uses the other system.

Travel and maps

Convert kilometres to miles to make sense of a distance abroad, or the other way round.

School and work

Answer a homework or spec question that mixes metric and imperial units.

Instant, exact & 100% in your browser

The conversion runs right here in your browser using exact, standard factors. Nothing you type is sent to a server, there is no sign-up and no limit, and once the page has loaded it keeps working even with no connection.

Frequently asked questions

How many centimetres are in an inch?: Exactly 2.54 centimetres, by definition, which makes one inch 25.4 millimetres. That fixed relationship is what every length conversion between the two systems is built on, so converting cm to inches simply divides by 2.54.
What is a nautical mile?: A nautical mile is 1,852 metres, a little longer than a regular mile of 1,609.344 metres. It is used at sea and in the air because it relates neatly to lines of latitude, with one nautical mile being about one minute of latitude.
How accurate are the conversions?: Each conversion uses the exact, internationally defined factor for the unit, not a rounded approximation, so the maths is precise. The result is shown to several significant figures and rounded only for display. For everyday and most professional use, the figures are exact to well beyond the precision you need.
Does this work offline and is anything sent to a server?: The conversion runs entirely in your browser, so nothing you type is sent anywhere, and once the page has loaded it keeps working with no connection. There is no sign-up and no limit on how many conversions you make.