A 144° angle is an obtuse angle: wider than a right angle (90°) but less than a straight line (180°). Its supplement is 36°, so a 144° angle and a 36° angle side by side make a straight line.
144° is 2/5 of a full circle, or 4π/5 radians. The minute hand of a clock sweeps 144° in 24 minutes. If you face north and turn 144° clockwise, you end up facing between SE and SSE (closest to southeast (SE)).
144° angle facts
| Angle type | Obtuse angle (between 90° and 180°) |
|---|---|
| Supplement (adds to 180°) | 36° |
| Explement (adds to 360°) | 216° |
| Radians | 4π/5 ≈ 2.513274 |
| Gradians | 160 grad |
| Fraction of a turn | 2/5 (40%) |
| Degrees, minutes, seconds | 144° 0′ 0″ |
| Compass bearing | between SE and SSE (closest to southeast (SE)) |
Trigonometric values of 144°
| Function | Value |
|---|---|
| sin 144° | √(10 − 2√5)/4 ≈ 0.587785 |
| cos 144° | −(√5 + 1)/4 ≈ −0.809017 |
| tan 144° | −0.726543 |
144° on a protractor
How to draw a 144° angle with a protractor
- Draw a straight line with a ruler. This is the first arm; mark the vertex at one end.
- Place the center mark of the protractor exactly on the vertex and line up the 0° baseline with your line.
- Find 144° on the row of numbers that reads 0° on your line (protractors have two rows running in opposite directions) and make a small dot at the edge.
- Remove the protractor and draw a line from the vertex through the dot. Mark the angle with an arc and label it 144°.
Drawing it a 144° angle without a protractor (rise and run method)
- 144° = 180° − 36°. Draw a straight line, pick a vertex on it, and build a 36° angle on one side as follows; the angle on the other side of the new line is 144°.
- Draw a straight baseline and measure exactly 10 inches along it from the vertex.
- At the 10-inch mark, draw a short line straight up at 90° (use a carpenter's square or the corner of a sheet of paper).
- Measure 7.27 inches (about 7 1/4″) up that line and make a mark.
- Join the mark to the vertex. The angle at the vertex is 36°, because tan 36° ≈ 0.7265.
Where you see 144° angles
- Each interior corner of a regular decagon measures 144°.
- The Earth turns 144° on its axis in about 9 h 36 min.
- Obtuse angles like 144° appear in reclining chair backs, open laptop screens, fan blades, and the corners of many-sided polygons.
Related angles
144° angle FAQ
What type of angle is 144°?
A 144° angle is an obtuse angle, because it is between 90° and 180°.
What is the supplement of 144°?
The supplement of 144° is 36°, because 144° + 36° = 180°. A 144° angle has no complement, because it is already larger than 90°.
How many radians is 144 degrees?
144° = 4π/5 radians ≈ 2.5133 rad. To convert degrees to radians, multiply by π/180: 144 × π/180 = 4π/5.
How do I measure a 144° angle on my screen?
Open the online protractor with 144° preset, or type 144 into its "Type an angle" box. You can then drag the arms onto your own lines to compare.
