Name

Math.ceil() — round a number up

Synopsis

Math.ceil(x)

Arguments

x

Any numeric value or expression.

Returns

The closest integer greater than or equal to x.

Description

Math.ceil() computes the ceiling function—i.e., it returns the closest integer value that is greater than or equal to the function argument. Math.ceil() differs from Math.round() in that it always rounds up, rather than rounding up or down to the closest integer. Also note that Math.ceil() does not round negative numbers to larger negative numbers; it rounds them up toward zero.

Example

a = Math.ceil(1.99);   // Result is 2.0
b = Math.ceil(1.01);   // Result is 2.0
c = Math.ceil(1.0);    // Result is 1.0
d = Math.ceil(-1.99);  // Result is -1.0

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