km から mm 変換ツール - キロメートル から ミリメートル

Conversion derivation

Express both km and mm in the same base unit m (meter), then cancel the shared base unit.

1. 1

   Rewrite km in the base unit

   $$1\mathrm{km}=1,000\mathrm{m}$$
2. 2

   Rewrite mm in the base unit

   $$1\mathrm{mm}=0.001\mathrm{m}$$
3. 3

   Forward conversion

   $$\begin{array}{rl}1\mathrm{km}& =\frac{1,000\cancel{\mathrm{m}}}{0.001\cancel{\mathrm{m}}}\times 1\mathrm{mm}\\ & =\frac{1,000}{0.001}\mathrm{mm}\\ & =1,000,000\mathrm{mm}\end{array}$$
4. 4

   Reverse conversion

   $$\begin{array}{rl}1\mathrm{mm}& =\frac{0.001\cancel{\mathrm{m}}}{1,000\cancel{\mathrm{m}}}\times 1\mathrm{km}\\ & =\frac{0.001}{1,000}\mathrm{km}\\ & =0.000001\mathrm{km}\end{array}$$