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JavaScript parseFloat() Function
JavaScript Global Functions
Definition and Usage
The parseFloat() function parses a string and returns a floating point number.
This function determines if the first character in the specified string is a number. If it is, it parses the string until it reaches the end of the number, and returns the number as a number, not as a string.
Syntax
parseFloat(string)
| Parameter | Description |
|---|---|
| string | Required. The string to be parsed |
Browser Support
The parseFloat() function is supported in all major browsers.
Tips and Notes
Note: Only the first number in the string is returned!
Note: Leading and trailing spaces are allowed.
Note: If the first character cannot be converted to a number, parseFloat() returns NaN.
Example
Example
Parse different strings:
<script>
document.write(parseFloat("10") + "<br>");
document.write(parseFloat("10.33") + "<br>");
document.write(parseFloat("34 45 66") + "<br>");
document.write(parseFloat(" 60 ") + "<br>");
document.write(parseFloat("40 years") + "<br>");
document.write(parseFloat("He was 40") + "<br>");
</script>
document.write(parseFloat("10") + "<br>");
document.write(parseFloat("10.33") + "<br>");
document.write(parseFloat("34 45 66") + "<br>");
document.write(parseFloat(" 60 ") + "<br>");
document.write(parseFloat("40 years") + "<br>");
document.write(parseFloat("He was 40") + "<br>");
</script>
The output of the code above will be:
10
10.33
34
60
40
NaN
10.33
34
60
40
NaN
Try it yourself »
JavaScript Global Functions
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