The **`toPrecision()` method** rounds a number to a specified precision or significant digits. If the rounded number requires more digits than the original number, the method adds decimals and nulls to create the specified format.  

If the `toPrecision()` method is called on an object other than a number, a `TypeError` occurs. 

# Syntax
The `toPrecision()` method is declared as follows:


# Parameters
The `toPrecision()` method takes an optional single parameter `x`, which is an integer number representing the number of significant digits. 

* If the value of `x` is not within the range 0 - 100, a `RangeError` occurs. 

* If `x` is not an integer, it is rounded to the nearest integer. 


# Return value
The `toPrecision()` method returns a string rounded to `x` significant digits. If `x` is not specified, the number is returned in string form without any rounding. 

# Examples
The following code shows the use of the `toPrecision()` method in JavaScript:


//Example 1
var num = 1.234567;
console.log(num.toPrecision());
//Example 2
console.log(num.toPrecision(4));
//Example 3
console.log(num.toPrecision(2));
//Example 4
console.log(num.toPrecision(1));

What is the toPrecision() method in JavaScript?

Syntax

Parameters

Return value

Examples