JavaScript String_trim Guide
String trimming removes whitespace from ends of strings for cleaning user input and normalizing text. The guide walks through Trim Methods. `str.trim()` — remove whitespace both ends. `str.trimStart()` / `str.trimEnd()` — one side. Whitespace: spaces, tabs, newlines, non-breaking spaces. Use for: cleaning form input, normalizing file paths, processing CSV data. Remove all spaces: `str.replace(/\s+/g, "")`. Collapse spaces: `str.replace(/\s+/g, " ").trim()`. 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.