Number typed variables hold numeric values and include a number of methods (built in functions) for performing numeric operations.
Number variables are declared by simply assigning a numeric value to a variable, or using the Number constructor.
var myNumber = 46;
var myNumber = Number(46);
Once a variable of the Number type has been declared with a numerical value, the toFixed() method is available to format it to a specified number of decimal places.
The toFixed() method will format a number to a fixed number of decimal places/digits. Here’s the Syntax:
- toFixed() does NOT modify the original number value/variable it is called from
- A STRING containing the formatted number is returned!
- digits is an optional parameter
- If it is not provided, a default value of 0 will be used
- The number will be rounded if necessary
- Zeros will be appended if necessary to reach the required number of decimal places
toFixed() Method Code Examples
let myNumber = 12345.6789 myNumber.toFixed() // Returns '12346': Note rounding to nearest integer as default number of decimal places is 0 myNumber.toFixed(1) // Returns '12345.7': Note number is rounded myNumber.toFixed(6) // Returns '12345.678900': Note zeros added to the end to reach number of desired decimal places (1.23e+20).toFixed(2) // Returns '123000000000000000000.00' (1.23e-10).toFixed(2) // Returns '0.00' 2.34.toFixed(1) // Returns '2.3' 2.35.toFixed(1) // Returns '2.4': Note number rounded up 2.55.toFixed(1) // Returns '2.5': Note number rounded down -2.34.toFixed(1) // Returns -2.3 : Note that due to operator precedence, a string is not returned as the '-' operator has coerced the value back to a number (-2.34).toFixed(1) // Returns '-2.3': Note, above situation avoided as '-' operator is bracketed
Floating Point Numbers Warning
It’s also worth keeping in mind that floating point numbers are not always accurately represented by computers – check out our article on why this is and how to avoid running into the commonly associated problems.