Use Number.isFinite() to check for a number in JavaScript

Need the best way to check for a number in JavaScript while excluding NaN or Infinity? Try Number.isFinite() instead of typeof.

Hi Octavian Theodor Nita, thanks for reminding me to take another look at Sumer Singh’s response — number.isFinite() is great!

I really appreciate you reading my article and for your response to it!

Indeed, Number.isFinite() is the most convenient way to check for a number in JavaScript, as it excludes NaN, Infinity, and -Infinity:

I updated my article on checking for a number in JavaScript to recommend Number.isFinite() and to note that there is also the global isFinite() function, which will coerce values to numbers before the check.

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