All tools

• tester

  Regex Tester & Explainer

  Test regular expressions against sample text with live match highlighting, and get a plain-English breakdown of what the pattern actually does.

• tester

  Text Diff Checker

  Compare two blocks of text side by side or unified, with word-level highlighting inside changed lines, whitespace/case-insensitive options, and a copyable unified diff.

• tester

  JSON Diff Checker

  Compare two JSON documents structurally — ignores key order, highlights real value changes in a tree, and exports a JSON Patch (RFC 6902).