Mermaid Diagram Renderer Paste mermaid.js syntax and instantly see a live, interactive diagram you can copy or download. Supports flowcharts, sequence diagrams, Gantt charts, pie charts, class diagrams, and more — all rendered client-side in your browser, with no servers, accounts, or installs required. Mermaid is great for “diagrams as code”: your diagram lives next ...
Try the Tool »Makefile Formatter Paste a Makefile and the formatter normalizes it to GNU make’s strict tab-indented recipe rules. Recipe lines that use spaces instead of tabs (the most common cause of “missing separator” errors and a frequent issue with AI-generated Makefiles) are repaired automatically. Trailing whitespace, runaway blank lines, and inconsistent assignment spacing are cleaned up ...
Try the Tool »Java Properties File Formatter This tool formats Java .properties files using the same rules the JDK uses to load them. It accepts =, :, or whitespace as a separator, recognises both # and ! comment styles, and joins backslash continuation lines into clean single-line key/value pairs. Use it on application.properties, logback.properties, ResourceBundle messages_*.properties, or any ...
Try the Tool »NDJSON Formatter & Validator Paste a Newline-Delimited JSON (NDJSON / JSON Lines) document and check every record at once. Each line is parsed independently, so a single broken record does not hide the rest. The tool reports valid and invalid line counts, the most common top-level keys, and the exact parse error for any line ...
Try the Tool »SVG to React JSX Component Converter Paste raw SVG markup and get a clean React functional component back. The tool applies deterministic camelCase conversion for every attribute, drops non-JSX syntax, and wraps the output in a ready-to-import component — optionally typed, optionally forwardRef-wrapped, and optionally resized via props. Everything runs locally in your browser, so ...
Try the Tool »CSV to XML Converter Turn any CSV file into clean, well-formed XML without leaving the browser. Paste or upload your data, pick how rows and headers should map, and get back properly escaped XML with the entity edge cases (ampersands, angle brackets, quotes, embedded newlines) handled automatically. Everything runs client-side, so your CSV never leaves ...
Try the Tool »Git Unified Diff & Patch Generator Paste an original snippet and a modified snippet to instantly generate a valid unified diff in .patch format. The output uses correct hunk headers (@@ -L,N +L,N @@) so the patch applies cleanly with git apply or the standard patch utility — no hand-fixing required. How to Use Paste ...
Try the Tool ».editorconfig Generator Build a valid, spec-compliant .editorconfig file for your project without memorising property names or cross-checking values. Pick a preset for your language, tweak the global defaults, toggle a few per-language overrides, and copy the result straight into the root of your repository. EditorConfig files keep indent styles, line endings, character sets, and trailing-whitespace ...
Try the Tool »Morse Code Audio Player Type any text and listen to it played as real Morse code in your browser. Adjust the speed and tone to match practice exam standards or vintage CW radio gear, then download the result as a WAV file you can use offline. How to Use Type or paste any letters, numbers, ...
Try the Tool »LLM Token Count Estimator Paste any prompt, document, or snippet of code and instantly see an estimated token count for GPT-4o, GPT-4 Turbo, GPT-3.5, the o1 reasoning models, Claude 3.x, and Gemini 1.5. The tool runs fully in the browser, updates in real time as you type, and pairs the count with cost figures per ...
Try the Tool »Semver Version Calculator & Range Tester An all-in-one Semantic Versioning (SemVer 2.0.0) workbench for developers. Validate version strings, compare two versions with strict precedence, test whether a version satisfies an npm/Composer-style range expression (^, ~, x, hyphen, ||, comparison operators), bump a version with major/minor/patch/prerelease increments, and sort large lists of versions with full pre-release ...
Try the Tool »XPath Expression Tester & Evaluator Paste XML or HTML, type an XPath 1.0 expression, and instantly see which nodes match. The tester runs entirely in your browser, highlights matched fragments in the source, and shows a readable summary for node sets, strings, numbers, and booleans. How to Use Paste your XML or HTML document into ...
Try the Tool »README Badge Generator The README Badge Generator builds pixel-perfect Shields.io-style badges directly in your browser. Pick a preset or craft your own label and message, choose colors and a style (flat, flat-square, for-the-badge, or plastic), and get copy-ready Markdown, HTML, SVG, and data URL output. No external API calls, no network dependency, no broken badges ...
Try the Tool »Reading Time Calculator Quickly estimate how long it will take to read any text, whether silently or aloud. This free online reading time calculator analyzes your text and provides accurate time estimates based on adjustable words-per-minute (WPM) speeds, along with word and character counts. How to Use Paste your text into the input area or ...
Try the Tool »HTML Meta Tag Generator Generate complete HTML meta tags for your web pages in seconds. This tool helps you create SEO meta tags, Open Graph tags for Facebook and LinkedIn, and Twitter Card tags — all from a single, easy-to-use interface. Simply fill in your page details and copy the generated code into your HTML ...
Try the Tool »Phone Number Parser and Formatter Parse and format phone numbers into standard international formats instantly. Enter any phone number in any format and get it converted to E.164, national, international, and RFC 3966 formats. The tool also detects the country, validates the number, and identifies the number type (mobile, fixed line, toll-free, etc.). How to ...
Try the Tool »List Converter The List Converter tool lets you instantly convert lists between different formats. Whether you have a newline-separated list that needs to become a comma-separated string, a JSON array, an HTML list, or an SQL IN clause, this tool handles the conversion with a single click. It also offers options to trim whitespace, remove ...
Try the Tool »Email Normalizer The Email Normalizer tool standardizes email addresses by applying common normalization rules. It removes dots from Gmail-style local parts, strips plus (+) aliases, converts addresses to lowercase, and removes duplicates. This is useful for deduplication, data cleaning, and identifying unique email accounts. How to Use Enter one or more email addresses, one per ...
Try the Tool »Regex Cheatsheet A comprehensive, searchable quick reference guide for regular expression syntax and common patterns. Whether you are writing validation rules, parsing log files, or doing text transformations, this cheatsheet gives you instant access to the regex patterns you need. How to Use Browse through the categorized tables to find the regex syntax you need. ...
Try the Tool »Citation Generator Quickly generate properly formatted academic citations in APA 7th, MLA 9th, Chicago 17th, and Harvard styles. Enter your source details — whether it’s a book, journal article, website, or conference paper — and get a correctly formatted citation instantly. How to Use 1. Select your source type (Book, Journal Article, Website, or Conference ...
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Scoreboard is a fun way to keep track of your games, all data is stored in your browser. More features are coming soon!
Update: Our latest tool was added on May 27, 2026
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