Angle Calculator: Complementary, Supplementary, Triangle and Clock Angles
Pick what you need, enter the angle (or the time) and get the answer with a diagram and the working.
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Complementary angle
55°
- In radians
- 0.9599 Radians
- Supplementary angle
- 145 °
- To make 360°
- 325 °
Show working
- 90° − 35° = 55°
How to use
- Choose complementary, supplementary, third angle or clock.
- Enter the angle, the two triangle angles, or the hour and minute.
- Read the answer and the steps.
Good to know
Complementary angles add up to 90° and supplementary angles to 180° (NCERT Class 7 "Lines and Angles"). The explement (or conjugate) is what is left to make 360°.
The three angles of a triangle add up to 180°, so the third angle is 180° − A − B. The exterior angle at that corner equals the sum of the two opposite interior angles.
Clock angle: the minute hand moves 6° a minute and the hour hand 0.5° a minute, so the angle is |30H − 5.5M|. If it is over 180°, the smaller angle is 360° minus it. This comes up often in SSC, bank and railway reasoning papers.
Questions
What is the complement of 35°?
90° − 35° = 55°.
What is the supplement of 35°?
180° − 35° = 145°.
What is the angle between the clock hands at 3:40?
|30 × 3 − 5.5 × 40| = |90 − 220| = 130°.
Can an obtuse angle have a complement?
No. Only angles less than 90° have a complement.
Is anything I enter stored?
No. The calculation runs in your browser and nothing is sent to a server.