String Toolkit — Online String Modifier & Editor
Transform, analyze, extract, clean, split and manipulate text strings — all in one place. Change case, trim, deduplicate, reverse, count and more, instantly in your browser.
What can this string editor do?
The String Toolkit bundles the most common text operations into a single tool: case conversion (UPPER, lower, Title Case, camelCase, snake_case, kebab-case), trimming whitespace, removing duplicate or blank lines, reversing text, counting characters/words/lines, find & replace, and extracting substrings.
Private and instant
Every transformation runs client-side in your browser — nothing is uploaded to a server, so you can safely paste sensitive text.
String formatting examples
Paste text into the input pane, choose a tool from String Tools, then run it. For example, uppercase conversion changes:
Hello developer → HELLO DEVELOPER
Removing duplicate lines keeps one copy of each repeated line:
apple banana apple → apple banana
Review the output before copying it. The workspace offers case conversion, whitespace cleanup and other transformations without needing to leave this page.
Frequently asked questions
What can the String Toolkit do?
Change case, trim whitespace, dedupe lines, reverse text, count characters/words/lines, find & replace, extract substrings, and more — all in one tool.
Is this string editor free to use?
Yes, completely free with no signup required.
Does my text get uploaded to a server?
No — all processing happens locally in your browser.