Maps scales can be expressed as a ratio or as a distance on the ground to a distance on a map.
For example, Ordnance Survey Landranger maps are 1:50,000. This means that 1cm on the map is 0.5km (or 500m which is 50,000cm) on the ground.
In the UK, we tend to look at distances in miles and maps in inches. The following is a list of scales and their approximate ‘Miles to Inches’ conversions:
| Map Scale | Miles to Inches |
|---|---|
| 1:10,000 | 1 mile = 6.25 inches |
| 1:11,400 | 1 mile = 5.5 inches |
| 1:14,000 | 1 mile = 4.5 inches |
| 1:15,000 | 1 mile = 4.2 inches |
| 1:20,000 | 1 mile = 3 inches |
| 1:25,000 | 1 mile = 2.5 inches |
| 1:42,000 | 1 mile = 1.5 inches |
| 1:63,000 | 1 mile = 1 inch |
| 1:100,000 | 1.6 miles = 1 inch |
| 1:126,700 | 2 miles = 1 inch |
| 1:150,000 | 2.4 miles = 1 inch |
| 1:200,000 | 3 miles = 1 inch |
| 1:253,000 | 4 miles = 1 inch |
| 1:300,000 | 5 miles = 1 inch |
| 1:350,000 | 5.5 miles = 1 inch |
| 1:435,000 | 7 miles = 1 inch |
| 1:500,000 | 8 miles = 1 inch |
| 1:515,000 | 8.15 miles = 1 inch |
| 1:560,000 | 9 miles = 1 inch |
| 1:625,000 | 10 miles = 1 inch |
| 1:760,000 | 12 miles = 1 inch |
| 1:800,000 | 12.6 miles = 1 inch |
| 1:900,000 | 14.2 miles = 1 inch |
| 1:1,000,000 | 16 miles = 1 inch |
| 1:1,250,000 | 20 miles = 1 inch |
| 1:1,500,000 | 24 miles = 1 inch |
| 1:2,000,000 | 32 miles = 1 inch |
| 1:2,500,000 | 39 miles = 1 inch |
| 1:3,000,000 | 47 miles = 1 inch |
| 1:3,250,000 | 51 miles = 1 inch |
| 1:3,500,000 | 55 miles = 1 inch |
| 1:3,750,000 | 59 miles = 1 inch |
| 1:4,000,000 | 63 miles = 1 inch |
| 1:5,000,000 | 79 miles = 1 inch |
| 1:5,800,000 | 92 miles = 1 inch |
| 1:6,000,000 | 95 miles = 1 inch |
| 1:10,000,000 | 158 miles = 1 inch |
| 1:15,000,000 | 237 miles = 1 inch |
| 1:20,000,000 | 316 miles = 1 inch |
| 1:30,000,000 | 473 miles = 1 inch |
| 1:40,000,000 | 631 miles = 1 inch |
