Angle Converter — Degrees, Radians, Gradians, DMS & More | LazyTools
📐 Angle Converter

Angle Converter — Degrees, Radians, Gradians & DMS

Convert between 13 angle units simultaneously — type in any field and all others update instantly. Includes DMS (degrees–minutes–seconds) compound input, a live unit circle visualiser, trig values, and common angles quick-fill. Free, no account.

13 units live DMS input Unit circle sin / cos / tan Pi notation
ADSENSE — 728×90 LEADERBOARD
📐 Angle Converter

Type any value — all 13 units + DMS update instantly

Enter an angle in any unit. The unit circle, trig values, and pi notation update live.

DMS — Degrees ° Minutes ’ Seconds ”
°
Standard Angle Units
Circle Subdivisions
Unit circle
90° 180° 270° cos sin
45°
= π/4 rad
Trigonometric values
sin0.7071
cos0.7071
tan1.0000
cot1.0000
sec1.4142
csc1.4142
Common angles — click to load
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Need to convert frequency or rotational speed?
The free Frequency Converter converts rad/s, RPM, Hz, kHz, MHz and 12 other units — pairs perfectly with the angle converter for angular velocity calculations.
📶 Frequency Converter →
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📖 How to Use

How to convert angle units

1
Enter any value
Type an angle into any of the 13 unit fields. All other units, the DMS compound field, the unit circle, and trig values update instantly.
2
Use DMS input
For geographic coordinates or precise measurements, enter degrees, minutes, and seconds separately in the DMS compound field at the top. All other units update from DMS too.
3
Load common angles
Click any of the 12 quick-fill buttons (0°, 30°, 45°, 60°, 90°, 120°, 135°, 150°, 180°, 270°, 360°, 1 rad) to instantly load that angle.
4
Read the unit circle
The unit circle updates live showing the angle position, a sector arc, and dashed projections for the cos (x-axis) and sin (y-axis) values. The exact pi fraction is shown below.
5
Check trig values
Sin, cos, tan, cot, sec, and csc for the current angle are shown in the trig panel. Undefined values (tan 90°) are flagged clearly.
6
Copy any value
Click the 📋 button next to any unit to copy its value. The DMS Copy button copies the full formatted DMS string.
✔ Key Features

The most complete free online angle converter

13 Units + DMS Live
All 13 angle units and the DMS compound field update simultaneously from any input. No button press, no waiting.
📐
Unit Circle Visualiser
Live SVG unit circle showing angle position, sector arc, and dashed sin/cos projection lines. Updates on every keystroke.
📏
DMS Compound Input
Dedicated degrees-minutes-seconds input with separate fields for D, M, S. Reads and writes simultaneously with all other units.
🧮
Trig Values
Live sin, cos, tan, cot, sec, and csc for the entered angle. Undefined values (tan 90°, sec 90°) are flagged with "undefined".
π
Pi Fraction Notation
Shows exact pi fractions for common angles: π/6, π/4, π/3, π/2, 2π/3, 3π/4, 5π/6, π, and multiples. Displayed below the unit circle.
📋
Copy Per Field
Individual copy button on each unit row. The DMS Copy button copies the full formatted string (e.g. 45°0'0") to clipboard.
🔔
12 Quick Angles
One-click load for all standard angles: 0°, 30°, 45°, 60°, 90°, 120°, 135°, 150°, 180°, 270°, 360°, and 1 radian.
🔓
Free, No Account
100% free with no signup, no limits, and no premium tier. Convert as many angles as you need without creating an account.
📐 Angle Guide

Angle Unit Conversion — Degrees, Radians, Gradians & DMS Complete Guide

Angles can be measured in many different units. Degrees are the most familiar — a full circle is 360°. Radians are the standard mathematical unit where a full circle equals 2π radians. Gradians (also called gon) divide a right angle into 100 parts, so a full circle is 400 grad. Each system has advantages depending on the application.

Conversion formulas

Degrees to radians
rad = deg x (π/180)
180° = π rad = 3.14159...
Radians to degrees
deg = rad x (180/π)
1 rad = 57.2958°
Degrees to gradians
grad = deg x (10/9)
90° = 100 grad
DMS to decimal degrees
DD = D + M/60 + S/3600
47°26'13" = 47.4369°
Decimal degrees to DMS
D = int(DD), M = int(frac x 60), S = frac(M) x 60
47.4369° = 47°26'13"
Degrees to arcminutes
arcmin = deg x 60
1° = 60 arcmin = 3600 arcsec

Standard angle reference table

DegreesRadians (exact)Radians (decimal)Gradianssincostan
000010
30°π/60.523633.330.50.86600.5774
45°π/40.7854500.70710.70711
60°π/31.047266.670.86600.51.7321
90°π/21.570810010undef.
120°2π/32.0944133.330.8660-0.5-1.7321
180°π3.141592000-10
270°3π/24.7124300-10undef.
360°6.2832400010

Why radians are used in mathematics and programming

Radians are the natural unit for angles in mathematics. The radian is defined so that an arc of length r on a circle of radius r subtends an angle of 1 radian at the centre. This makes calculus formulas for trigonometric functions simpler: the derivative of sin(x) is cos(x) only when x is in radians. Programming languages and scientific calculators use radians by default for sin(), cos(), tan() functions. To use degrees with these functions, you must convert first: sin(degrees * PI / 180).

Gradians (gon) — the metric angle

Gradians (also called gon or grades) were introduced as part of the metric system to make angle arithmetic easier. The key advantage: a right angle is exactly 100 gradians, so right-angle multiples (slopes, compass bearings) are round numbers. Gradians are used in surveying (particularly in Continental Europe), land navigation, and some military applications. A full circle = 400 grad. Half circle = 200 grad. 1 gradian = 0.9 degrees = π/200 radians.

DMS — Degrees, Minutes, Seconds

DMS is the traditional format for geographic coordinates and astronomical measurements. Just as hours are divided into 60 minutes and 60 seconds, degrees are subdivided similarly. The Moon is 384,400 km away; its angular diameter is approximately 31’6” (31 arcminutes 6 arcseconds). GPS coordinates are often expressed as DMS: 51°30’26”N, 0°7’39”W (the Tower of London). Converting DMS to decimal degrees: DD = D + M/60 + S/3600.

Milliradians in military and firearms

The milliradian (mrad) is used for targeting and range estimation. At 1000 metres, 1 mrad subtends approximately 1 metre — this is the practical mil rule used in sniper and artillery applications. Rifle scopes calibrated in mrad allow precise elevation and windage adjustments. NATO uses a slightly different mil (1/6400 of a circle — not a true milliradian) while the Warsaw Pact used 1/6000. This converter uses the true mathematical milliradian (1/1000 of a radian).

❓ FAQ

Angle converter FAQ

Multiply by pi/180 (approximately 0.017453). Examples: 90 x pi/180 = pi/2 = 1.5708 rad. 180 degrees = pi rad. 360 degrees = 2*pi rad. Type degrees into the converter above and radians update instantly.

Multiply by 180/pi (approximately 57.2958). Examples: pi rad = 180 degrees. pi/2 rad = 90 degrees. 1 radian = 57.2958 degrees. 2*pi rad = 360 degrees.

A gradian divides a right angle into 100 parts. Full circle = 400 grad. To convert degrees to gradians, multiply by 10/9. To convert gradians to degrees, multiply by 9/10 (= 0.9). Used in surveying and Continental European land navigation.

1 degree = 60 arcminutes ('). 1 arcminute = 60 arcseconds ("). So 1 degree = 3600 arcseconds. Used in astronomy, GPS accuracy, and optics. The Moon's diameter is about 31 arcminutes. 1 arcsecond on Earth's surface is about 30 metres.

DMS = Degrees-Minutes-Seconds. Example: 47 degrees 26' 13" = 47 + 26/60 + 13/3600 = 47.4369 decimal degrees. Used for GPS coordinates, astronomy, and navigation. The DMS input above converts automatically when you change any field.

Exactly 2*pi radians (approximately 6.28318). Key values: quarter circle = pi/2 = 1.5708 rad = 90 degrees. Half circle = pi = 3.14159 rad = 180 degrees. Three-quarter = 3*pi/2 = 4.71239 rad = 270 degrees.

Binary degrees divide a full circle into 256 units (2^8). 256 binary degrees = 360 degrees. 128 = 180 degrees. 64 = 90 degrees. Used in game engines and embedded systems where integer arithmetic is preferred for angle storage.

The LazyTools Angle Converter is 100% free with no signup. Convert between 13 units and DMS simultaneously, see the live unit circle and trig values, load common angles. No account, no limits.