JavaScript Convert String to Float
To convert a string to float in JavaScript, call parseFloat() function and pass the string as argument to it.
parseFloat() function returns a floating point number created from the given string.
The syntax to convert a string str
to a float is
parseFloat(str)
Examples
In the following example, we have taken a string in str
, and convert this string to float using parseFloat() function.
index.html
<!DOCTYPE html> <html lang="en"> <head> <meta charset="utf-8"> </head> <body> <div id="output"></div> <script> var str = '3.14'; var x = parseFloat(str); document.getElementById('output').innerHTML = 'Float : ' + x; </script> </body> </html>
Any spaces around the string will be implicitly trimmed by the parseFloat() function.
index.html
<!DOCTYPE html> <html lang="en"> <head> <meta charset="utf-8"> </head> <body> <div id="output"></div> <script> var str = ' 3.14 '; var x = parseFloat(str); document.getElementById('output').innerHTML = 'Float : ' + x; </script> </body> </html>
parseFloat() can also handle scientific notation of floating point number.
index.html
<!DOCTYPE html> <html lang="en"> <head> <meta charset="utf-8"> </head> <body> <div id="output"></div> <script> var str = '314e-2'; var x = parseFloat(str); document.getElementById('output').innerHTML = 'Float : ' + x; </script> </body> </html>
If there are any non-digit characters in the given string, those characters would be ignored by parseFloat() function.
index.html
<!DOCTYPE html> <html lang="en"> <head> <meta charset="utf-8"> </head> <body> <div id="output"></div> <script> var str = '3.14abcd'; var x = parseFloat(str); document.getElementById('output').innerHTML = 'Float : ' + x; </script> </body> </html>
Conclusion
In this JavaScript Tutorial, we learned how to convert a string into integer using parseFloat() function, with examples.