number formatting in JavaScript

What this snippet does

parseInt and parseFloat are lenient; Number() is strict — Number('42px') returns NaN while parseInt handles it.

Expected output

3.14
3.142
42
3.14
42
0

Why practise typing this

Typing numbers code builds muscle memory for the symbols and indentation JavaScript uses most, which prose-based typing tests never cover. DevType measures your words per minute and accuracy on this snippet and tracks the individual characters you mistype, so later lessons can target them.

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