Fast, free developer utilities that never send your data to a server.
Client-side developer utilities — format JSON, view JSON as Graph, create Markdown files, draw Mermaid diagrams, check regex, format code, and process text without sending data to a server.
Editors
View all →Mermaid Diagram Editor
Write and preview Mermaid diagrams with real-time SVG rendering, templates, and export.
Markdown Editor
Live Markdown editor with GFM table formatting, embedded Mermaid diagrams, and HTML export.
HTML/CSS/JS Playground
Live front-end sandbox to write HTML, CSS, and JavaScript with instant preview and console output.
JSON & Data
View all →JSON Formatter & Validator
Pretty-print, validate, and minify JSON with exact error locations.
JSON Tree Viewer
Explore JSON as a collapsible tree instead of a wall of text.
JSON to Graph Visualizer
Turn JSON files into an interactive node graph you can expand, collapse, zoom, and pan.
JSON to TypeScript
Generate TypeScript interfaces from a JSON sample.
Text & Strings
View all →Case Converter
Convert between camelCase, snake_case, kebab-case, and PascalCase.
Text Diff Checker
Compare two blocks of text and highlight the differences.
Word & Character Counter
Count words, characters, sentences, lines, and analyze reading time.
Slugify Tool
Generate clean, URL-safe slugs from titles and strings.
String Escape / Unescape
Escape and unescape HTML, JavaScript, JSON, Regex, URL, and SQL strings.
Sort, Dedupe & Line Tools
Sort alphabetically, natural, deduplicate, shuffle, reverse, and prefix lines.
Lorem Ipsum Generator
Generate placeholder text by paragraphs, sentences, words, or lists.