processconvert
Length and Area

kmtonm

Convert kilometres (km) to nanometres (nm).

Factor1 km = 1e+12 nm

Converter

km

Accepts numbers or expressions, e.g. 150 + 14.7

Result
1e+12nm

Rendered to 6 significant figures.

Formula

Formula
nm = km × 1e+12

Multiply any value in kilometres by 1e+12 to obtain the value in nanometres.

Worked example

Convert 1 km to nm.

  1. 01Start with 1 km.
  2. 02Multiply by the conversion factor: 1 × 1e+12 = 1e+12 nm.
Result1 km = 1e+12 nm

Conversion table

kmnm
11e+12
22e+12
55e+12
101e+13
202e+13
505e+13
1001e+14
2002e+14
5005e+14
10001e+15

Reference values rounded to 5 significant figures for display.

FAQ

What is the conversion factor from km to nm?
1 km equals 1e+12 nm. To convert, multiply the value in kilometres by 1e+12.
How do I convert 1 km to nm?
1 km = 1e+12 nm. For any value, multiply by 1e+12.
How do I convert nm back to km?
Divide by the same factor — or equivalently, multiply by 1e-12. So 1 nm = 1e-12 km.
When would I need to convert kilometre to nanometre?
Length conversions appear in piping, layout, and mechanical drawings — particularly when reconciling imperial fittings or instrument lengths with metric plant drawings.
Is the conversion exact?
Yes. Both km and nm are defined by exact SI relationships, so the displayed factor is exact (any rounding shown is only for display).

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