Is the Length Converter free?

Yes — the Length Converter is completely free, with no account, subscription, signup, or usage limits.

Is my data uploaded or stored?

No. The Length Converter processes everything locally in your browser. Your input is never uploaded, saved, or shared with any server.

Does the Length Converter work offline?

Yes. Once the page has finished loading, the Length Converter works without an internet connection.

Which browsers does the Length Converter work in?

The Length Converter works in all modern browsers, including Chrome, Firefox, Safari, and Edge — no plugins or extensions needed.

Does this free length converter support nautical miles?

Yes — nautical miles (nmi) are included alongside imperial and metric units.

Can I convert very small lengths like nanometres?

Yes — the tool supports nanometres (nm) and micrometres (μm) for scientific or optical applications.

Length Converter

Convert between metres, feet, inches, kilometres, miles, and more.

From

Millimetre (mm)

0.1

Centimetre (cm)

1 mm = 0.1 cm

All Conversions for 1 mm

Centimetre	cm	0.1
Metre	m	0.001
Kilometre	km	0.000001
Inch	in	0.03937007874
Foot	ft	0.003280839895
Yard	yd	0.001093613298
Mile	mi	6.213712e-7
Nautical Mile	nmi	5.399568e-7
Micrometre	μm	1000
Nanometre	nm	1000000
Light Year	ly	1.056971e-19

Free browser-based tool · Runs 100% on your device · Last updated July 7, 2026

What is the Length Converter?

The free Length Converter supports 12 units: millimetres (mm), centimetres (cm), metres (m), kilometres (km), inches (in), feet (ft), yards (yd), miles (mi), nautical miles (nmi), micrometres (μm), nanometres (nm), and light years (ly). Select a unit from the From dropdown, enter your measurement, and the To dropdown shows the converted value instantly. The All Conversions table below displays your value in every unit simultaneously — no calculator needed.

→ Converting feet to metres for construction or architecture
→ Converting kilometres to miles for road trips or fitness apps
→ Converting nanometres to micrometres for scientific or optical work
→ Converting inches to centimetres for clothing or screen sizes

How to Use the Length Converter

1 Select your source unit (e.g. ft) from the From dropdown.
2 Enter the length value in the input field.
3 Choose your target unit (e.g. m) from the To dropdown.
4 Read the instant result shown in the output field.
5 Click ⇄ Swap to reverse the direction.
6 Check the All Conversions table for all units at once.

Key Features

📏
12 length units

From nanometres all the way to light years — metric, imperial, and scientific units in one free tool.
⚡
Instant live conversion

Results update as you type — no submit button needed.
⇄
Swap button

Reverse From ↔ To in one click.
📊
All Conversions table

See your value in all 12 units at a glance.
🆓
Free, no login

100% browser-based — your data is never uploaded.

Example Usage

Example Input

From: ft · Value: 6 · To: m

Example Output

6 ft = 1.8288 m

Frequently Asked Questions about the Length Converter

What is the Length Converter?: The Length Converter is a free online tool that lets you convert between metres, feet, inches, kilometres, miles, and more. It runs entirely in your browser, so there is nothing to install and nothing is uploaded to a server.
Is the Length Converter free?: Yes — the Length Converter is completely free, with no account, subscription, signup, or usage limits.
Is my data uploaded or stored?: No. The Length Converter processes everything locally in your browser. Your input is never uploaded, saved, or shared with any server.
Does the Length Converter work offline?: Yes. Once the page has finished loading, the Length Converter works without an internet connection.
Which browsers does the Length Converter work in?: The Length Converter works in all modern browsers, including Chrome, Firefox, Safari, and Edge — no plugins or extensions needed.
Does this free length converter support nautical miles?: Yes — nautical miles (nmi) are included alongside imperial and metric units.
Can I convert very small lengths like nanometres?: Yes — the tool supports nanometres (nm) and micrometres (μm) for scientific or optical applications.