Length Converter

Kilometre to Millimetre
From
To
Reverse All Units

Converting between kilometres and millimetres is a common operation in engineering, construction, and science. Understanding how these units relate helps you work with measurements at different scales, from microscopic dimensions to vast distances.

Also convert to: m cm dm mm nm in ft yd mi nmi

42 km = 42 mm

42 (forty-two) kilometre(s) is equal to 42 (forty-two) millimetre(s)

What is kilometre?

The kilometre (km) is a metric unit equal to 1,000 metres. It is the standard unit for measuring road distances, travel distances, and geographic scales in most countries outside the United States. One kilometre equals approximately 0.621 miles.

What is millimetre?

The millimetre (mm) is a metric unit equal to one thousandth of a metre. It is widely used in engineering, manufacturing, and medicine for precise measurements. Standard paper thickness is typically measured in millimetres.

How to convert km to mm

To convert Kilometre to Millimetre, multiply the value by 1.
42 km × 1 = 42 mm

Common Conversions

km mm (Millimetre) Description
1 km 1 mm 1 Kilometre(s) = 1 Millimetre(s)
2 km 2 mm 2 Kilometre(s) = 2 Millimetre(s)
5 km 5 mm 5 Kilometre(s) = 5 Millimetre(s)
10 km 10 mm 10 Kilometre(s) = 10 Millimetre(s)
25 km 25 mm 25 Kilometre(s) = 25 Millimetre(s)
50 km 50 mm 50 Kilometre(s) = 50 Millimetre(s)
100 km 100 mm 100 Kilometre(s) = 100 Millimetre(s)
250 km 250 mm 250 Kilometre(s) = 250 Millimetre(s)
500 km 500 mm 500 Kilometre(s) = 500 Millimetre(s)
1000 km 1000 mm 1000 Kilometre(s) = 1000 Millimetre(s)
2500 km 2500 mm 2500 Kilometre(s) = 2500 Millimetre(s)
5000 km 5000 mm 5000 Kilometre(s) = 5000 Millimetre(s)
10000 km 10000 mm 10000 Kilometre(s) = 10000 Millimetre(s)

Convert Kilometre to other units

km Unit Description
42 km 42000 m Metre
42 km 4200000 cm Centimetre
42 km 4200 dm Decimetre
42 km 42 mm Millimetre
42 km 0.000042 nm Nanometre
42 km 1653543.307087 in Inch
42 km 137795.275591 ft Foot
42 km 45931.75853 yd Yard
42 km 26.09759 mi Mile
42 km 22.678186 nmi Nautical mile

More Millimetre conversions

1 km 2 km 3 km 4 km 5 km 6 km 7 km 8 km 9 km 10 km 11 km 12 km 13 km 14 km 15 km 16 km 17 km 18 km 19 km 20 km 25 km 30 km 40 km 50 km 60 km 70 km 80 km 90 km 100 km 200 km 300 km 500 km 1000 km 2000 km 5000 km 10000 km

Share this conversion