Text & Content Tools

Some jobs are about plain text: a regular expression that matches four of the five lines it should, two versions of a config file that look identical until you scroll, or a column of product names that need to become URL slugs.

The regex tester highlights every match as you type and lists the capture groups, so you can see which part of the pattern fails. The diff checker lines up two blocks of text and marks what was added, removed or left alone. The case converter switches between camelCase, snake_case, kebab-case, PascalCase and a few others in one click. The slug generator does the same job for URLs, including transliterating accented characters. The word counter reports characters, words, sentences, paragraphs and an approximate reading time. The Markdown editor renders as you type and gives you clean HTML at the end.

Everything runs in your browser tab. You can paste a draft, a customer list or half a production log, and none of it leaves your machine.

Which tool for which job

  • Find out why a pattern misses a line

    Regex Tester. Matches highlight as you type and capture groups are listed, using the JavaScript regex engine in your browser.

  • Compare two versions of a config file

    Diff Checker. Compare by line, word or character. Ignore whitespace hides changes that are only indentation or Windows line endings.

  • Compare two API responses whose key order differs

    JSON Diff. Both sides are parsed and compared by path, so reordered keys do not show up as changes.

  • Rename identifiers between camelCase and snake_case

    Case Converter. Each line is converted on its own, so you can paste a whole list of field names at once.

  • Make a URL slug from a title

    Slug Generator. Accented letters are transliterated, so Café Münster becomes cafe-munster.

  • Check a draft against a length limit

    Word & Character Counter. Characters, words, sentences and reading time update as you type.

  • Write a README with a live preview

    Markdown Editor & Preview. The preview renders as you type, and you can copy sanitized HTML when you are done.

  • Sort a list of file names or version numbers

    Sort Lines. Natural sort puts file2 before file10, which plain alphabetical sorting gets wrong.

  • Clean duplicates out of a list of emails or IDs

    Remove Duplicate Lines. Keep either the first or the last copy of each line.

  • Apply several replacements to a block of text

    Find and Replace. Plain and regex rules run in order, so one pass can do the work of several manual edits.

Other tool categories

Specifications and references

This tool follows the specifications below. Read them when you need the exact normative wording, for example to settle an edge case between two implementations.

Frequently Asked Questions

Which regex flavor does the tester use?

JavaScript's, through the RegExp engine in your browser. Most syntax carries over to PCRE (PHP), Python and Java, but some does not. Possessive quantifiers and atomic groups exist in PCRE and have no JavaScript syntax, and Python writes named groups as (?P<name>...). Test the final pattern in the language you ship.

What is natural sort order?

Natural sort compares the numbers inside text by their value. Alphabetical sorting compares character by character, so item10 comes before item2, because 1 sorts before 2. Natural sort gives item2, then item10, which is what people expect for file names, versions and numbered lists.

Should I compare JSON files with the Diff Checker or with JSON Diff?

Use JSON Diff when key order or formatting may differ, because it compares the parsed values by path. Use the Diff Checker when the exact text matters, for example to review a change to a committed JSON file line by line.

Copied to clipboard!