Comparisons in Javascript

So what’s the difference between == and === in Javascript? Nothing at all if the types on both ends are the same!

If they are different though, == will try to coerce, before compare and this is where a lot of confusion comes from.

42 == "42"; // true, "42" will be converted to number before comparison
1 == true; // true, because true will be converted to 1 before comparison

This also applies to relation comparisons like < and even <=.

There is no way to avoid coercion with relational comparisons. These are the only ones which are valid:

• < (less than)
• > (greater than)
• <= (less than or equal to)
• >= (greater than or equal to)
• == (equality with coercion)
• === (strict equality, no coercion)