A 101° angle is obtuse because it is greater than 90° and less than 180°. Its supplement is 79°, so a 101° angle and a 79° angle side by side make a straight line.
101° is 101/360 of a full circle, or 101π/180 radians. If you face north and turn 101° clockwise, you end up facing between E and ESE (closest to east (E)).
101° angle facts
| Angle type | Obtuse angle (between 90° and 180°) |
|---|---|
| Supplement (adds to 180°) | 79° |
| Explement (adds to 360°) | 259° |
| Radians | 101π/180 ≈ 1.762783 |
| Gradians | 112.2222 grad |
| Fraction of a turn | 101/360 (28.06%) |
| Degrees, minutes, seconds | 101° 0′ 0″ |
| Compass bearing | between E and ESE (closest to east (E)) |
Trigonometric values of 101°
| Function | Value |
|---|---|
| sin 101° | 0.981627 |
| cos 101° | −0.190809 |
| tan 101° | −5.144554 |
101° on a protractor
How to draw a 101° 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 101° 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 101°.
Drawing it a 101° angle without a protractor (rise and run method)
- 101° = 180° − 79°. Draw a straight line, pick a vertex on it, and build a 79° angle on one side as follows; the angle on the other side of the new line is 101°.
- Draw a straight baseline and measure 1.94 inches (about 1 15/16″) along it from the vertex.
- At that mark, draw a line straight up at 90° and measure exactly 10 inches up it.
- Join the top mark to the vertex. The angle at the vertex is 79°, because tan 79° ≈ 5.1446.
Where you see 101° angles
- The Earth turns 101° on its axis in about 6 h 44 min.
- Obtuse angles like 101° appear in reclining chair backs, open laptop screens, fan blades, and the corners of many-sided polygons.
Related angles
101° angle FAQ
What type of angle is 101°?
A 101° angle is an obtuse angle, because it is between 90° and 180°.
What is the supplement of 101°?
The supplement of 101° is 79°, because 101° + 79° = 180°. A 101° angle has no complement, because it is already larger than 90°.
How many radians is 101 degrees?
101° = 101π/180 radians ≈ 1.7628 rad. To convert degrees to radians, multiply by π/180: 101 × π/180 = 101π/180.
How do I measure a 101° angle on my screen?
Open the online protractor with 101° preset, or type 101 into its "Type an angle" box. You can then drag the arms onto your own lines to compare.
