Approximate Metric Equivalents for Degrees, Minutes, and Seconds

At the equator for longitude and for latitude anywhere, the following approximations are valid:

• 1° = 111 km  (or 60 nautical miles)
• 0.1° = 11.1 km
• 0.01° = 1.11 km (2 decimals, km accuracy)
• 0.001° =111 m
• 0.0001° = 11.1 m
• 0.00001° = 1.11 m
• 0.000001° = 0.11 m (7 decimals, cm accuracy)

• 1' = 1.85 km  (or 1 nautical mile)
• 0.1' = 185 m
• 0.01' = 18.5 m
• 0.001' = 1.85 m

• 30" = 900 m
• 15" = 450 m
• 3" = 90 m
• 1" = 30 m
• 1/3" = 10 m
• 0.1" = 3 m
• 1/9" = 3 m
• 1/27" = 1 m

If you report a position to the nearest 0.01°  (two decimal places for latitude and longitude), you will only be accurate to around 1 km.  While this is adequate for rough locations on a global scale, for detailed work it will be inadequate.

Last revision 5/8/2019