JavaScript · Junior · Question 66 of 75

How does `Number.isNaN("abc")` differ from `isNaN("abc")`?

✓Correct answer: Number.isNaN gives false (it's a string, not NaN); global isNaN converts first and gives true
2Both return true
3Both return false

Explanation

The global isNaN coerces its argument, which leads to surprises. Number.isNaN checks only for the actual NaN value.

Further reading

javascript.info: Numbers ↗

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