regular expression to match exactly 5 digits

Question

I am reading a text file and want to use regex below to pull out numbers with exactly 5 digit, ignoring alphabets.

Try this…

var str="f 34 545 323 12345 54321 123456",
    matches = str.match(/\b\d{5}\b/g);

console.log(matches); // ["12345", "54321"]

jsFiddle.

The word boundary \b is your friend here.

My regex will get a number like this 12345, but not like a12345. The other answers provide great regexes if you require the latter.