Kilometres to Micrometres Converter

Convert kilometres (km) to micrometres (µm) instantly. Enter a value in kilometres and this converter returns the equivalent in micrometres, using the exact factor of 1,000,000,000. One kilometre is 1,000,000,000 micrometres, and one micrometre is 1.000000e-9 kilometres, so you can convert either way. The factor follows the standard definitions of the metre and the international inch, so it is consistent and reliable for school work, trade, engineering, travel and everyday measuring. The formula, a worked example and a quick-reference table are below.

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Value in kilometres (km)

1 km =1,000,000,000 µm

1 µm =1.000000e-9 km

The formula

Multiply kilometres by 1,000,000,000 to get micrometres. In symbols, µm = km × 1,000,000,000. To go the other way, multiply micrometres by 1.000000e-9 to get kilometres.

Worked example

Convert 10 kilometres to micrometres: 10 × 1,000,000,000 = 10,000,000,000 micrometres.

Quick reference

Kilometres	Micrometres
1 km	1,000,000,000 µm
2 km	2,000,000,000 µm
5 km	5,000,000,000 µm
10 km	10,000,000,000 µm
25 km	25,000,000,000 µm
50 km	50,000,000,000 µm
100 km	100,000,000,000 µm

Frequently asked questions

How many micrometres are in one kilometre?

One kilometre equals 1,000,000,000 micrometres. Multiply the number of kilometres by 1,000,000,000 to convert.

What is the formula to convert kilometres to micrometres?

Kilometres times 1,000,000,000 equals micrometres. To reverse it, multiply micrometres by 1.000000e-9 to get kilometres.

Is the km to µm conversion exact?

The factor comes from the standard definitions of the metre and the international inch (0.0254 m exactly), so the underlying conversion is exact. Displayed results are rounded for readability.

Who this converter is for

This converter is for students, tradespeople, travellers and anyone who needs to change kilometres into micrometres quickly and accurately.

What this converter assumes

You enter a length in kilometres.
The factor used is 1,000,000,000 micrometres per kilometre.
Results are rounded for display.

Sources

Related converters

Length Converter: convert between any length units.
Unit Converter: convert many kinds of units.
Kilometres to Inches Converter: convert kilometres to inches.
Kilometres to Feet Converter: convert kilometres to feet.

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