The angle that, added to your input, equals 180 degrees (or pi radians)
Supplementary angle unitdeg
Angle sum180
sin(angle)0.866
cos(angle)0.5
tan(angle)1.7321
sin(angle)0.866
cos(angle)0.5
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The supplement of 60 deg is 120.0000 deg.
Your angle (60.00 deg) is acute, so its supplement (120.00 deg) is obtuse.
Trig shortcut: sin(60.0 deg) = sin(120.0 deg) = 0.8660. The sines of supplementary angles are always equal.
Supplementary angles appear constantly in geometry: co-interior angles in parallel lines, adjacent angles on a straight line, and opposite angles in cyclic quadrilaterals all use the 180-degree relationship.
Next stepIf you need the angle that adds to 90 degrees instead of 180 degrees, use the complementary angles calculator.