parse Int

Turn text that has just number characters into an integer number value.


You can change a text string having number characters into an actual integer value. The text needs to have only number characters. This can also include the '-' and the '.' symbols though. But, only the integer part (left of the decimal point) is converted to a number.

If the text has other characters, like "-2g5u7", only -2 is returned since it is the best attempt at converting to a number. So, try not to mix number characters with letters or other symbols.

Powers of 10

If the text string has the letter ‘e’ after the number characters and then some more number characters like “2e4”, then the number characters after the ‘e’ are an exponent of 10. This means that a string with "8e3" becomes the value of 8000 when converted to an integer. This is because the 2 after the e is 2 powers of ten which is 10 * 10 * 10 or 1000. The resulting value then is 8 * 1000 which equals 8000.


  • an integer number value for the text number in the string.


Take the temperature text from the sentence and turn it into a number.

let frozenWater = "The freezing temperature of water is 32 degrees Fahrenheit.";
let freezing = parseInt(frozenWater.substr(37, 2));

See also

parse float