Convert between metric units of length - m & km
Theory
A kilometre is \(1000\) metres. To change kilometres to metres, multiply by 1000; to change metres to kilometres, divide by 1000. This Year 6 maths page shows how to convert whole and decimal distances, such as \(2.75\) km \(= 2750\) m, and how to compare and order distances given in different units.
Kilo means one thousand, so \(1\) km \(= 1000\) m. Kilometres are used for distances between places; metres for shorter distances such as running tracks.
km to m: multiply by \(1000\) (the digits move \(3\) places left): \(2.75\) km \(= 2750\) m.
m to km: divide by \(1000\) (the digits move \(3\) places right): \(4300\) m \(= 4.3\) km; \(45\) m \(= 0.045\) km.
Useful facts: \(200\) m \(= 0.2\) km, \(100\) m \(= 0.1\) km, \(10\) m \(= 0.01\) km.
Metres and kilometres:
How to convert
- km to m: multiply by \(1000\).
- m to km: divide by \(1000\).
- Check: the number of metres should be bigger than the number of kilometres.
How to compare distances
- Write every distance in metres.
- Compare or order the numbers, then write the answer in the original units.
| \(6 \times 1000\) | \(=\) | \(6000\) |
\(6000\) m.
| \(9000 \div 1000\) | \(=\) | \(9\) |
| \(4300 \div 1000\) | \(=\) | \(4.3\) |
\(9\) km and \(4.3\) km.
(i) \(0.6\) km
(ii) \(2.75\) km
| \(0.6 \times 1000\) | \(=\) | \(600\) |
| \(2.75 \times 1000\) | \(=\) | \(2750\) |
(i) \(600\) m
(ii) \(2750\) m
| \(45 \div 1000\) | \(=\) | \(0.045\) |
\(0.045\) km.
(ii) Five laps of a \(400\) m track: how many kilometres?
| \(18 \times 1000\) | \(=\) | \(18\,000\) |
| \(5 \times 400\) | \(=\) | \(2000\) |
(i) \(18\,000\) m
(ii) \(2000\) m \(= 2\) km
(i) Who went further?
(ii) By how many metres?
| \(4.6 \times 1000\) | \(=\) | \(4600\) |
| \(4750 - 4600\) | \(=\) | \(150\) |
(i) Ben
(ii) \(150\) m
In metres: \(2100\), \(1950\), \(2015\).
\(1950\) m, \(2015\) m, \(2.1\) km.
| \(3400 \div 1000\) | \(=\) | \(3.4\) |
There are \(1000\) m in a kilometre, so divide by \(1000\): \(3.4\) km.
Common pitfalls
Frequently asked questions
How many metres are in a kilometre?
\(1000\).
How do I change km to m?
Multiply by \(1000\): \(2.75\) km \(= 2750\) m.
How do I change m to km?
Divide by \(1000\): \(4300\) m \(= 4.3\) km.
What is 200 m in kilometres?
\(0.2\) km.
How do I compare 4.6 km and 4750 m?
Change to metres: \(4600\) m is less than \(4750\) m.