Developer Tools
Format code and structured data, test expressions, and generate practical development assets.
27 available tools
JSON Formatter
Format, validate, or minify JSON locally in your browser.
Developer ToolsFull-width & Half-width Converter
Convert ASCII characters between full-width and half-width forms.
Developer ToolsUUID Generator
Generate one or many cryptographically random UUID v4 values.
Developer ToolsRandom Number Generator
Generate secure random integers within a selected range.
Developer ToolsUnix Timestamp Converter
Convert Unix timestamps to ISO dates or dates to Unix seconds.
Developer ToolsJSON & Query String Converter
Convert a JSON object to URL query parameters or restore JSON.
Developer ToolsJSON & CSV Converter
Convert arrays of JSON objects to CSV or parse CSV as JSON.
Developer ToolsHTML Formatter & Minifier
Format readable HTML or minify it locally in your browser.
Developer ToolsJavaScript Formatter & Minifier
Format JavaScript with Prettier or minify it with Terser.
Developer ToolsCSS Formatter & Minifier
Format CSS with Prettier or minify it with CSSO.
Developer ToolsSQL Formatter
Format SQL statements or produce a more compact layout.
Developer ToolsXML Formatter & Minifier
Validate and format XML or remove formatting whitespace.
Developer ToolsXML & JSON Converter
Convert XML documents to JSON or JSON values to XML.
Developer ToolsYAML & JSON Converter
Convert YAML documents to JSON or JSON values to YAML.
Developer ToolsJava Formatter
Format Java source code locally with a parser-based formatter.
Developer ToolsUBB & HTML Converter
Convert common UBB tags to safe HTML or HTML tags back to UBB.
Developer ToolsRegular Expression Tester
Test JavaScript regular expressions and inspect every match.
Developer ToolsXPath Expression Tester
Evaluate XPath expressions against XML documents locally.
Developer ToolsMarkdown Editor
Write Markdown and preview sanitized HTML in real time.
Developer ToolsScreen PPI Calculator
Calculate pixel density from resolution and diagonal screen size.
Developer ToolsBatch Link Generator
Convert one URL per line into HTML anchors or Markdown links.
Developer ToolsBatch URL Opener
Validate a list of web addresses and open them from one page.
Developer ToolsWeb Font Tester
Preview text using CSS font-family, size, weight, spacing, and line height.
Developer ToolsTest Data Generator
Generate fictional user records as JSON or CSV for development and testing.
Developer ToolsJSON / Postman Bulk Edit Converter
Convert flat JSON objects to Postman bulk-edit key-value lines and back.
Developer ToolsChina Resident ID Validator
Validate the structure, birth date, checksum, province code, and encoded sex of an 18-digit ID number.
Developer ToolsName & Number Fortune Game
Generate a deterministic, entertainment-only reading from a name, word, or number.