Text Tools
7 free tools · 100% client-side
Text tools that run in your browser: convert case and clean up lines, compare two texts, convert Markdown to HTML and back, and decode Unix timestamps.
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Most-used Text Tools
String Utility
Sixteen everyday text operations in one tool — case conversion, line sorting and deduping, whitespace cleanup, counts.
Text Diff
Paste two versions, see what changed — matching lines aligned, insertions and deletions highlighted, nothing uploaded anywhere.
Markdown to HTML
Paste Markdown, get the HTML a Markdown renderer would produce — GitHub Flavored tables, task lists, fenced code and strikethrough included.
All 7 Text Tools
String Utility
Sixteen everyday text operations in one tool — case conversion, line sorting and deduping, whitespace cleanup, counts.
Markdown to HTML
Paste Markdown, get the HTML a Markdown renderer would produce — GitHub Flavored tables, task lists, fenced code and strikethrough included.
HTML to Markdown
Turn CMS exports, documentation pages and pasted markup into clean Markdown — wrappers and inline styling dropped, tables and code blocks kept.
Epoch Converter
Paste a timestamp in seconds or milliseconds — or a date string — and get every form of the same instant at once, without ever consulting the clock.
Text Diff
Paste two versions, see what changed — matching lines aligned, insertions and deletions highlighted, nothing uploaded anywhere.
YAML Diff
Two YAML documents side by side with syntax highlighting, so an indentation change reads as a structural change rather than as moved whitespace.
XML Diff
Two XML documents side by side with markup highlighting, so an attribute edit reads differently from a text-node edit at a glance.
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The text jobs that sit between two other tools
Most developer work on text is not editing prose — it is reshaping it just enough to hand to the next thing. A column of identifiers has to move from camelCase to snake_case before it becomes a database migration. A pasted log extract needs its ragged whitespace trimmed and its duplicate lines dropped before it becomes a SQL IN clause. A README written in Markdown has to become HTML for a CMS that never learned Markdown, or a block of CMS-exported HTML has to become Markdown so it can live in a repository. Two config files that are supposed to be identical have to be put side by side to find the one line that is not. An expiry claim of 1788998400 has to become a date before you can tell whether the token is the problem. Every one of those is a thirty-second job, and every one of them costs five minutes if you have to go and find a tool for it.
This hub collects them. The String Utility bundles sixteen one-click text transforms — eight case conversions sharing a single tokenizer that treats camel humps, underscores, hyphens and spaces alike as word boundaries, plus line sorting, reversing, deduplication and whitespace cleanup, plus a counter that reports characters, words, lines and UTF-8 bytes. The Markdown and HTML converters run the same engines the ecosystem uses — marked in one direction, turndown in the other — so GitHub Flavored Markdown tables, task lists, fenced code blocks and strikethrough all survive the trip rather than collapsing into paragraphs. The Epoch Converter reads a Unix timestamp in seconds or milliseconds, or an ISO or RFC date string, and reports every form of the same instant at once: UTC ISO 8601, RFC 2822, weekday, day of year, ISO week date, seconds, milliseconds, microseconds and the Excel serial number that spreadsheets use.
Three diff checkers, because format-aware diffing reads better
The comparison tools deserve their own note. Text Diff, YAML Diff and XML Diff are the same side-by-side editor with the same alignment algorithm, differing only in the syntax highlighting each pane applies — and that difference is worth more than it sounds. A YAML diff with YAML highlighting makes an indentation change visible as a structural change rather than as a run of moved spaces; an XML diff with markup highlighting separates an attribute edit from a text-node edit at a glance. Text Diff, with no highlighting at all, is the right tool for everything else: environment variable lists, log extracts, license headers, CSV rows, two versions of a prompt, two copies of a paragraph.
All three align matching lines and mark insertions, deletions and modifications inline, so unchanged regions collapse out of the way and your eye lands on the difference immediately. If the two sides are JSON rather than free text or markup, JSON Compare understands the format better still, and sorting both documents' keys first removes the ordering noise that would otherwise dominate the result.
Private by construction, like the rest of the site
Text is where secrets hide. Internal hostnames, customer names in a log extract, a JWT's expiry claim, an environment file being diffed against production, a draft that has not been published — the reason these tools run entirely in your browser tab is that this is exactly the category of data nobody should paste into a server-backed site. Every transformation here is client-side JavaScript: nothing is uploaded, nothing is logged, and each page keeps working after you disconnect from the network, which is the simplest proof of the claim.
The tools also chain naturally with their neighbours. Extract values with the Regex Tester, then dedupe and sort them in the String Utility. Decode a token with the JWT Decoder, then paste its `exp` claim into the Epoch Converter to see the date in every format at once. Convert a Markdown table to HTML here, then run the result through the HTML Formatter before it goes into a template.
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Frequently asked questions
Everything you need to know about the Text Tools.
01What can the String Utility do?
Case conversions (camelCase, PascalCase, snake_case, kebab-case, Title Case, Sentence case, UPPER and lower), line operations (sort A→Z or Z→A, reverse, deduplicate, trim each line, remove line breaks, collapse extra spaces), and counts (characters, words, lines, and UTF-8 bytes). Each operation is a single click on whatever is in the editor, and the result re-runs when you switch operations.
02Which diff tool should I use — Text, YAML or XML?
Pick the one that matches your content, because the only difference is the syntax highlighting each pane applies, and highlighting is what makes a structural change readable. YAML Diff for manifests, pipelines and values files; XML Diff for POMs, feeds, SOAP envelopes and configuration; Text Diff for everything else — logs, env lists, CSV rows, prose. For JSON specifically, JSON Compare is the better-fitting page.
03Do the Markdown converters handle GitHub Flavored Markdown?
Yes, in both directions. Markdown to HTML renders GFM tables, task lists, strikethrough and autolinks by default (with a toggle to fall back to plain CommonMark), and HTML to Markdown emits ATX headings, fenced code blocks and GFM pipe tables with column alignment preserved. Round-tripping a simple document through both directions returns what you started with, modulo list-marker spacing.
04Why is the Epoch Converter's output the same every time I load it?
Because it never reads the current clock. Everything it reports — the UTC forms, weekday, day of year, ISO week date, the seconds/milliseconds/microseconds conversions and the Excel serial — is a pure function of the timestamp you paste, which makes the output stable, quotable in a bug report, and identical for you and for whoever you send it to.
05Are these tools private like the rest of the site?
Identical guarantee: every transformation runs in your browser tab with no uploads and no logging. Paste internal hostnames, customer lists, token claims, or unpublished drafts without any of it leaving your machine — the pages keep working offline once loaded.
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Guides for text tools
Regular Expressions Explained: A Practical Cheat Sheet With Tested Examples
A practical regex cheat sheet: metacharacters, quantifiers, groups, lookarounds and JavaScript flags, with tested patterns for emails, dates and slugs.
7 min readGuide · Developer ToolsCron Expression Syntax Explained: Fields, Special Characters and Real Schedules
Cron syntax field by field: ranges, the * , - / characters, the day-of-month OR day-of-week rule, DST pitfalls, and Quartz's six-field variant.
6 min readGuide · Developer ToolsUUID v4 vs UUID v7: Which Should You Use for Database Keys?
UUID v4 and v7 compared: why random v4 keys fragment B-tree indexes, how v7's timestamp fixes it, the collision math, and how to generate and store both.
7 min readGuide · Data FormatsYAML Anchors, Aliases and Merge Keys Explained (With Real Config Examples)
How &anchor, *alias and the <<: merge key work in YAML, where docker-compose, GitLab CI and Helm use them, the override order, and the errors they cause.
7 min readGuide · Data FormatsJSON vs YAML: Which Format When?
JSON vs YAML compared honestly: syntax, comments, whitespace pitfalls, tooling, and performance — with clear rules for when each format wins.
2 min readTutorial · Data FormatsYAML Tutorial: Read and Write It Without Fear
Learn YAML properly: mappings, lists, multi-line strings, anchors — and the indentation and typing pitfalls that break Kubernetes and CI configs.
2 min read