Angle Calculator

This calculator takes one angle in degrees and derives every other common way of describing it: radians (multiply by pi over 180), gradians (multiply by 10 over 9, since a full turn is 400 gradians instead of 360 degrees), the complementary angle (90 degrees minus the input), the supplementary angle (180 degrees minus the input), and the three primary trig ratios evaluated at that angle. Sine and cosine move in opposite directions across the 0 to 90 degree range the default value sits inside — as the angle rises, sine climbs toward 1 while cosine falls toward 0 — which is a genuine, checkable property of the two functions rather than a coincidence of this particular page. Tangent gets special handling: at 90 degrees and 270 degrees, and any angle 180 degrees apart from those, the geometric ratio is undefined because cosine sits at exactly zero in the denominator, so the calculator reports the word undefined instead of an enormous or infinite number that would be misleading to read as data.

The input itself is not restricted to a clean multiple of anything — entering 45.3 degrees works exactly like entering 45, because nothing in the underlying formulas rounds the angle before using it; the whole-number stepper on the field is a convenience for dragging the slider, not a constraint the calculation enforces. Angles outside minus 360 to 360 degrees fall outside the field's configured range and are not exercised here.