Mil Converter (NATO 6400, Warsaw Pact 6000, degrees)

Understanding the mil (angular) converter — concept and principle

The military "mil" is a unit of angle used for artillery, mortars, map compasses and range estimation. Different armies divide the circle differently: NATO uses 6,400 mils, the former Warsaw Pact used 6,000, and Sweden historically used 6,300 "streck". Rifle scopes marked "MIL" use the true milliradian, about 6,283 per circle. This converter switches between all of these and degrees.

Armies cut the circle into 6,400 or 6,000 parts; only the milliradian is a true 1/1000 radian.

How it is calculated

Every unit is converted to NATO mils and then to the target: result = value × (NATO mils per "from" unit) ÷ (NATO mils per "to" unit). Because each unit is a fixed fraction of a full circle:

1 NATO mil = 360° ÷ 6,400 = 0.05625°
1 Warsaw Pact mil = 360° ÷ 6,000 = 0.06°
1 Swedish streck = 360° ÷ 6,300
1 milliradian = 0.001 rad = 0.18 ÷ π ≈ 0.0573°
1° = 6,400 ÷ 360 ≈ 17.78 NATO mils

The principle

All mils are designed around the small-angle rule: an angle of 1 milliradian seen at a distance of 1,000 m spans 1 m. In general, size ≈ distance × angle (in radians), so a known target size and a measured angle give the range. A true milliradian divides the circle into 2π × 1,000 ≈ 6,283.19 parts, an awkward number. Armies rounded it to a convenient figure: 6,400 is easy to halve repeatedly (3,200, 1,600, 800 …), while 6,000 divides neatly by 10 and 60. These rounded mils are close to the milliradian but not equal, so a NATO mil is about 1.8% smaller.

Worked example

Inputs: value = 100, from NATO mils, to degrees.
100 × 360 ÷ 6,400 = 5.625°.
Warsaw Pact mils: 100 × 6,000 ÷ 6,400 = 93.75.
Milliradians: 100 × 2π × 1,000 ÷ 6,400 = 98.17477042.
Swedish streck: 100 × 6,300 ÷ 6,400 = 98.4375.

How to read the result

Rough benchmarks: a right angle is 1,600 NATO mils or 1,500 Warsaw Pact mils. With the small-angle rule, 1 NATO mil at 1,000 m spans about 0.98 m, against exactly 1 m for a milliradian. If a 2 m tall object spans 2 mrad in a scope, it is about 1,000 m away. Always confirm which mil a compass or sight uses before mixing readings.

Common mistakes

Assuming a scope's MIL reticle uses NATO mils; scopes use milliradians.
Mixing NATO and Warsaw Pact compass readings, which differ by more than 6%.
Applying the small-angle rule to large angles, where it becomes inaccurate.

Keep in mind: This converter is for education and general navigation. Real fire control, survey and targeting work uses specified equipment, procedures and corrections that go well beyond a unit conversion.

Frequently asked questions

How many degrees is 1 NATO mil?

Exactly 0.05625°.

Is a scope MIL the same as a NATO mil?

No. A scope MIL is a milliradian, about 0.0573°, roughly 1.9% larger than a NATO mil.

How many mils is a full circle?

6,400 NATO mils, 6,000 Warsaw Pact mils, 6,300 streck, or about 6,283.19 milliradians.

Sources: BIPM, The International System of Units (SI Brochure), 9th edition, 2019 (radian definition) · NIST Special Publication 811 (2008), Appendix B

Checked 8 Nov 2026. Factors from the SI Brochure (BIPM, 9th ed.) and NIST Special Publication 811 (2008), Appendix B.