Map Scale Calculator
Turns a measurement on a map into a real distance, and the other way round. If you know both, it gives the scale.
Share sends a link that reopens these numbers. Copy details pastes the full breakdown as a list.
The formula
ground distance = map distance × N map distance = ground distance ÷ N N = ground distance ÷ map distance
N has no unit: it compares two lengths in the same unit.
What to watch out for
A scale only holds for a flat measurement. A path on hilly ground is longer than it looks on the map, and a string or wheel measure follows bends better than a ruler.
Frequently Asked Questions
What does 1:25,000 mean?
One unit on the map is 25,000 of the same unit on the ground, so 1 cm covers 250 m and 4 cm covers 1 km.
How do I find the scale of a map?
Measure something of known length. If a 1 km stretch of road is 2 cm on the map, the scale is 1:50,000.