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# JavaScript - Math.ceil() method example

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The `Math.ceil()` function returns integer value that is greater than or equal to the argument - result of round up operation.

``````// ONLINE-RUNNER:browser;

console.log( Math.ceil(  5     ) ); //  5

console.log( Math.ceil(  2.49  ) ); //  3
console.log( Math.ceil(  2.50  ) ); //  3
console.log( Math.ceil(  2.51  ) ); //  3

console.log( Math.ceil( -2.49  ) ); // -2
console.log( Math.ceil( -2.50  ) ); // -2
console.log( Math.ceil( -2.51  ) ); // -2

console.log( Math.ceil(  0.999 ) ); //  1
console.log( Math.ceil(  1.001 ) ); //  2
console.log( Math.ceil( -1.001 ) ); // -1``````

## 1. Documentation

 Syntax `Math.ceil(number)` Parameters `number` - integer or float number value (primitive value). Result Rounded up `number` value (primitive value). If input `number` value is equal to `NaN` it returns `NaN`. If input  `number` value is equal to `-Infinity` it returns `-Infinity`. If input  `number` value is equal to `+Infinity` it returns `+Infinity`. Description `ceil` is static method that takes only one parameter and return rounded up value.

## 2. Rounding with precision up-to `n` places example

``````// ONLINE-RUNNER:browser;

function ceilPrecised(number, precision) {
var power = Math.pow(10, precision);

return Math.ceil(number * power) / power;
}

// Example:

console.log( ceilPrecised(     5  ,  0 ) ); // 5
console.log( ceilPrecised(     5. ,  0 ) ); // 5
console.log( ceilPrecised(      .5,  0 ) ); // 1

console.log( ceilPrecised(  1.1234,  0 ) ); // 2
console.log( ceilPrecised(  1.1234,  1 ) ); // 1.2
console.log( ceilPrecised(  1.1235,  2 ) ); // 1.13
console.log( ceilPrecised(  1.1235,  3 ) ); // 1.124

console.log( ceilPrecised( -1.1234,  0 ) ); // -1
console.log( ceilPrecised( -1.1234,  1 ) ); // -1.1
console.log( ceilPrecised( -1.1234,  2 ) ); // -1.12
console.log( ceilPrecised( -1.1234,  3 ) ); // -1.123

console.log( ceilPrecised(    1234, -1 ) ); // 1240
console.log( ceilPrecised(    1234, -2 ) ); // 1300
console.log( ceilPrecised(    1234, -3 ) ); // 2000

console.log( ceilPrecised(  5_000.000_001,  0 ) ); // 5001
console.log( ceilPrecised(  5_000.000_001,  6 ) ); // 5000.000001
console.log( ceilPrecised(  5_000.000_001, -3 ) ); // 6000``````

## References

1. Floor and ceiling functions - Wikipedia