Complete guide to text tools

By the inyourbrowser.com editorial team · Reviewed and tested September 30, 2026

What are text tools?

Text tools are utilities that read plain text, transform it, and return plain text. The category covers find and replace, line sorting, diffing, case conversion, word counting, placeholder generation, and readability scoring. Each tool runs locally so paste-heavy editing stays responsive.

How to choose a text tool

Name the change the text needs. Each change below points to one tool.

• If one string has to change everywhere it appears, replace every match in one pass. Turn on Whole word so “cat” leaves “category” alone, and switch to regex mode when the target follows a pattern, such as dates or trailing spaces.
• If a pasted list has repeats, remove the duplicate lines. With Keep original order selected, each line that remains keeps its place; matching ignores letter case. To reorder as well, sort A to Z, by leading number so 10 follows 9, or by length.
• If you have two versions of a text, see which words changed. The word view suits edited prose, side-by-side puts the versions in two columns, and the git-style view marks whole lines with plus and minus signs, as in code review. Either side can come from a text file.
• If a name has to follow another convention, convert it to snake_case or another style. The identifier styles (camelCase, PascalCase, snake_case, kebab-case) join the whole input into one name, so convert one name at a time; Title Case, UPPER CASE and lower case keep line breaks, so a list of headings converts at once. To swap the new name in everywhere, use find and replace with Whole word and Case sensitive on.
• For a web address, generate a URL slug instead: the slug generator turns café into cafe, while kebab-case keeps the accent.
• If a form caps the length, check the character count next to the word count. Characters are shown with and without spaces, so confirm which the limit means. A hyphenated term counts as one word.
• If the length is right but the text feels dense, score its grade level. The checker's other modes give a Flesch reading ease score (higher is easier) and reading times at 150, 238 and 350 words per minute.
• If the layout is ready before the copy, generate placeholder paragraphs as HTML, each in a paragraph tag, or as plain paragraphs, sentences or words.

For a side-by-side comparison with online grammar checkers and word processors, see the text tools overview.

Tool comparison

How to transform text in the browser

1. Pick the right transformation. Decide whether you need to replace substrings, sort lines, diff two versions, change capitalization, count units, or score readability.
2. Paste the source text. Paste the text into the input area. Most tools update immediately as you type or paste.
3. Configure options. Set the regex flag, the sort order, or the case style. The output adjusts as each option changes. Text diff has one page per view: word, side-by-side and git-style.
4. Copy or download. Use the Copy button where the tool has one, or select the result in the output box and copy it. The Lorem Ipsum generator can also download its output as a .txt or .html file.

Common workflows

Clean up an exported email list. Paste the dump in and strip the inline names with a regex, then sort and deduplicate the addresses, and read the line count above the sorted output to see how many entries remain.

Polish a blog post. Check the grade level against your target, fix recurring typos in one pass, and confirm the final length.

Review a code rename. Compare the old and new versions side by side, normalize the identifier casing, and confirm that no stray identifiers remain.

Mock up an article page. Fill the layout with placeholder paragraphs, check the length with the word and character counts, then paste in the real copy and score its reading level.

Rejoin broken lines. Text copied from a PDF's text layer often breaks after every printed line. In regex mode, find (?<!\n)\n(?!\n) and replace it with a space: lone line breaks become spaces, and blank lines, such as the one the PDF text extractor leaves between pages, stay. The walkthrough shows how to clean up text pulled from a PDF from extraction to the final paste.

Specification primer

Text on the web is Unicode, almost always encoded as UTF-8. JavaScript strings are sequences of UTF-16 code units, so most operations are transparent for English but surrogate pairs (emoji, supplementary scripts) need code-point-aware iteration.

Diff algorithms typically compute the longest common subsequence between two token streams. The text diff tool uses a longest-common-subsequence algorithm in a Web Worker so the UI stays responsive even on large inputs.

Readability formulas such as Flesch, Gunning Fog, and SMOG approximate reading difficulty from word and sentence length. They are useful heuristics for editorial work, not replacements for human review.

Frequently asked questions

What is a text tool?

Any utility that reads plain text, transforms it, and returns plain text. The category includes find and replace, line sorting, side-by-side and inline diffing, case conversion, word and character counting, placeholder generation, and readability scoring.

Does find and replace support regular expressions?

Yes. The tool offers a regex mode in addition to plain literal search, with case-sensitive and whole-word toggles. Capture groups and back-references work in the replacement string.

How does the diff tool handle very large inputs?

Diffing runs in a dedicated Web Worker so the main thread stays responsive. Lines that match at the start and end are set aside first, so a small change in a multi-megabyte file is found exactly; a changed region over 12,000 lines per side or 1.5 MB is marked as not compared.

Which case styles does the converter support?

camelCase, PascalCase, snake_case, kebab-case, Title Case, lower case, and UPPER CASE. For camelCase, PascalCase, snake_case and kebab-case the tool splits the input at spaces, punctuation and camelCase boundaries, so it converts from any of these styles to the one you select. Title Case, lower case and UPPER CASE change the letters in place and keep the spacing and punctuation.

Are words counted the same way as the spec for academic papers?

Words are counted as runs of non-whitespace characters, and each Chinese or Japanese character counts as one word. Hyphenated compounds and contractions count as one word. Word, character, sentence, and paragraph counts appear together so you can match whichever metric your style guide requires.

What is a Flesch reading ease score?

A 0 to 100 scale where higher numbers mean easier reading. 60 to 70 is the range targeted by most general-audience writing. The grade-level score complements it with a US school grade estimate.

How random is the lorem ipsum generator?

The generator builds sentences and paragraphs from a fixed bank of classical lorem ipsum words. Each click on Generate starts from a new random point in the bank, so the word sequence changes, but the vocabulary itself is constant.

Can these tools work with non-Latin scripts?

Mostly. JavaScript strings are full Unicode, so find and replace, sorting, diffing and case conversion work with Arabic, Cyrillic, CJK and combining diacritics, and line sorting uses the browser's locale-aware comparison so accented and non-Latin characters order sensibly. Two limits: the readability checker is calibrated for English and shows no score when most words are in another script, and the word counter counts each Chinese or Japanese character as one word.

Related concepts

• Regular expression backs find-and-replace and the regex tester.
• Diff algorithm explains how a text diff finds added and removed lines.
• Word boundary is the idea behind whole-word matching in find and replace.
• Developer tools guide covers regex testing in code-focused workflows.
• Data tools guide handles structured-data cleanups that follow text edits.

Reviewed and tested September 30, 2026.