SIN

SIN(angle) takes radians, not degrees: =SIN(RADIANS(30)) is 0.5. Worked examples, the conversion people forget, and the rounding you will see. Matches Excel.

Syntax

SIN(number)
Argument Required Description
number Required The angle, in radians.

Examples

Every example below was executed against VisiGrid engine 0.54.0 — not transcribed from another vendor's documentation. Reproduce any of them with vgrid calc.

Formula Result Notes
=SIN(PI()/2) 1 A quarter turn.
=SIN(RADIANS(30)) 0.50 Thirty degrees, converted to radians first.
=SIN(30) -0.99 Thirty radians, not thirty degrees — the most common mistake with this function.
=SIN(PI()) 0.00 Not exactly zero. See below.

Radians, not degrees

Every trigonometric function here takes radians, as in Excel and Sheets. Passing degrees does not produce an error — SIN(30) returns a perfectly valid number, just the sine of thirty radians. Wrap degree values in RADIANS:

=SIN(RADIANS(30))  → 0.50

Why SIN(PI()) shows 0.00

π cannot be stored exactly, so SIN(PI()) is the sine of a number very slightly off π — about 0.0000000000000001. The cell shows 0.00 rather than 0, which is the tell that a tiny residue is there.

It rarely matters. Comparisons with = allow for rounding at the fifteenth significant figure, so the residue does not break a test:

=SIN(PI())=0  → TRUE

Excel compatibility

Matches Excel. Angles are in radians.

Related functions

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