String.trim() Trim whitespace
Last updated: 2026-09-09
String.trim() Trim whitespace
trim strips leading and trailing whitespace — typical for cleaning user input.
| Category | Strings |
|---|---|
| ES version | ES5 |
📝 Syntax
const clean = str.trim();Returns：A new string without leading/trailing whitespace.
Mutates the original：No (returns a new value)
▶ Example
Edit the code, press Run, and see the result in the output panel:
Output：
admin@test.com
javascript
left
right💡 Tip Always trim user input before validation.
ℹ️ info trim only touches the edges — collapse inner whitespace with replace(/\s+/g, ' ').
🌐 Browser support
| Browser |  Chrome |
 Edge |
 Firefox |
 Safari |
 Opera |
|---|---|---|---|---|---|
| String.trim() | ✓ v1 | ✓ v12 | ✓ v1 | ✓ v1 | ✓ v1 |
| Supported by all modern browsers | |||||
🏷️ Related Items
💡 Related Cases
More case studies coming soon — check back later.
📚 Related Tutorials
❓ FAQ
QDoes trim remove inner spaces?
ANo — edges only. Collapse inner whitespace with replace(/\s+/g, ' ').
QWhat are trimStart and trimEnd?
AOne-sided variants (ES2019): trimStart trims the head, trimEnd the tail. trim = both.
QWhich characters does trim remove?
ASpaces, tabs, newlines and all Unicode whitespace.
