JavaScript Number_parse Guide
Number parsing with parseInt, parseFloat, and Number constructor for converting strings to numbers safely. The guide walks through Parsing Numbers. `parseInt("42")` = 42. `parseInt("42px")` = 42 (ignores trailing). `parseInt("101", 2)` — binary. `parseFloat("3.14")` = 3.14. `Number("42")` — strict (returns NaN for "42px"). `+"42"` — same as Number(). `isNaN(value)` — checks if value IS NaN (coerces). `Number.isNaN(value)` — strict (no coercion). The guide is organized into 1 sections that build on each other, each pairing a prose explanation with runnable code. Related guides: Arrays, Strings, Numbers, Math, Date. This is one of 145 JavaScript guides on JS Reference — see the full list on the guides page. Practice what you learn in the JavaScript playground, and look up any unfamiliar term in the JavaScript glossary.