Trim Whitespace Text
Remove leading and trailing whitespace from every line.
Trim Whitespace is a free online tool that remove leading and trailing whitespace from every line. It runs entirely in your web browser using plain JavaScript, so files are processed on your own device and never uploaded to a server. There is no sign-up, no file size limit imposed by the site, no watermark and no paid tier.
- Price
- Free — no account, no quota, no watermark
- Category
- Text
- Where it runs
- In your browser, on your device
- Files uploaded
- None
- Technology
- plain JavaScript
- Settings
- 1
- Works offline
- Yes, after the first visit
About Trim Whitespace
Leading and trailing whitespace is stripped from each line while whitespace inside the line is left alone. Trailing whitespace is the invisible defect that shows up as a diff on a line nobody touched, breaks Markdown in a way that is genuinely hard to see (two trailing spaces are a line break), and triggers linter failures in CI.
How to use it
- Paste the text you want to run through trim whitespace.
- Set trim.
The one setting
| Setting | What it does | Default |
|---|---|---|
| Trim | Choose from 3: Both ends, Start only, End only. | Both ends |
Under the hood
| Runs on | plain JavaScript — runs the whole thing |
| Controls | Trim |
Questions
Does it remove indentation?
Yes — leading whitespace is leading whitespace. If you are cleaning code and want indentation kept, use the trailing-only option.
Why does trailing whitespace matter?
It creates diff noise, changes Markdown rendering, and fails linters. Most editors can show or strip it automatically, and most projects enforce its absence.
What does the trim option change?
It offers 3 choices — Both ends, Start only and End only. The default is Both ends, which suits most cases; change it when your input or your destination calls for something specific.