JSON and Data Formatting
Validate, format, explore trees, convert, and compare JSON, YAML, and CSV documents side-by-side.
Developer Tools
22 toolsFormat code, inspect data structures, validate syntax, compare JSON, and debug expressions in your browser.
Popular Developer Tools tools
Start with the tools people use most often in this category.
UUID / GUID GeneratorGenerate secure, cryptographically random Version 4 (v4) and time-ordered Version 7 (v7) UUIDs and GUIDs with custom formatting, bulk batch generation, and live inspection.Markdown Preview & EditorLive preview, edit, and convert Markdown (.md) documents online. Supports GitHub Flavored Markdown (GFM), tables, task lists, code blocks, HTML export, and real-time word counting.JSON Formatter & ValidatorFormat, beautify, validate, and minify JSON data online with instant syntax error highlighting and tree inspection.JSON Tree ViewerExplore, navigate, and inspect complex JSON payloads with an interactive collapsible tree viewer, type badges, node search, and JSON path copying.Code to Image ConverterTransform source code snippets into gorgeous, shareable images for Twitter, LinkedIn, blog posts, and presentations with customizable gradient backgrounds and themes.JavaScript MinifierCompress, shrink, and minify JavaScript and ECMAScript code online. Strip whitespace and comments while preserving strings and regex literals for faster web page loads.URL Slug GeneratorTransform titles, headings, and product names into clean, SEO-friendly URL slugs with custom separators, stop word removal, and accent transliteration.HTML Encoder / DecoderEncode special characters into safe HTML entities or decode HTML entities back into plain readable text with support for named, decimal, and hex entities.JSON Validator & Syntax LinterValidate JSON syntax online with line and column error indicators, RFC 8259 compliance checks, structure tree inspection, and one-click auto-repair for common syntax errors.CSS Formatter & BeautifierFormat, beautify, and minify CSS code online. Clean up messy stylesheets, indent rules, sort CSS properties alphabetically, and compress stylesheet files client-side.JavaScript Formatter & BeautifierFormat, beautify, and minify JavaScript and TypeScript code online. Clean up indentation, standardize semicolons and quotes, and compress scripts 100% in your browser.JSON to YAML / YAML to JSON ConverterConvert JSON to YAML and YAML to JSON online. Fast bi-directional serialization with indentation control, syntax error checking, and zero server uploads.JSON to CSV / CSV to JSON ConverterConvert JSON to CSV and CSV to JSON online. Transform array records into spreadsheet-compatible CSV tables with delimiter options, nested object flattening, and instant download.XML Formatter & BeautifierFormat, beautify, and minify XML, SOAP, SVG, and RSS documents online. Fix tag indentation, format XML trees, compress markup, and validate syntax 100% in your browser.Base64 Encode & DecodeEncode and decode Base64 text and binary data online with UTF-8 character support, URL-safe Base64, and instant clipboard copying 100% in your browser.JWT Debugger & DecoderDecode, inspect, and verify JSON Web Tokens (JWT) online. View claims, expiration dates, signature verification, and build tokens safely 100% in your browser.cURL to Code ConverterConvert cURL command lines into production-ready code snippets for JavaScript Fetch, Axios, Python Requests, Go net/http, PHP cURL, and Node.js.SQL Formatter & BeautifierFormat, beautify, and minify SQL queries online. Standardize uppercase keywords, indent joins and subqueries, and clean syntax client-side with zero data sent to external servers.JSON Diff & Compare OnlineCompare two JSON structures side-by-side with automatic key sorting, colored difference highlights, and change breakdown.Regex Tester & Debugger OnlineTest, evaluate, and debug regular expressions in real-time with visual match highlights, capture group inspection, and quick regex cheat sheets.HTML Formatter & BeautifierFormat, beautify, and minify HTML, XML, and SVG markup with clean indentation, comment stripping, and real-time live preview.
Browse by task
Choose a workflow to find the most relevant tools faster.
Code Beautifiers, Markdown & Images
Preview Markdown files, generate beautiful code screenshots, compress JavaScript bundles, and format CSS, HTML, XML, and SQL.
URL, Encoders & Security Tools
Generate SEO URL slugs, encode/decode HTML entities, generate UUID/GUID tokens, test JWT tokens, and translate cURL requests.
Regex and Automation
Test regular expressions, debug match groups, and interpret cron schedule expressions.
All Developer Tools Tools
Showing 22 toolsUUID / GUID Generator
Generate secure, cryptographically random Version 4 (v4) and time-ordered Version 7 (v7) UUIDs and GUIDs with custom formatting, bulk batch generation, and live inspection.
Open tool →
JSON Formatter & Validator
Format, beautify, validate, and minify JSON data online with instant syntax error highlighting and tree inspection.
Open tool →
JSON Tree Viewer
Explore, navigate, and inspect complex JSON payloads with an interactive collapsible tree viewer, type badges, node search, and JSON path copying.
Open tool →
JSON Validator & Syntax Linter
Validate JSON syntax online with line and column error indicators, RFC 8259 compliance checks, structure tree inspection, and one-click auto-repair for common syntax errors.
Open tool →
Code to Image Converter
Transform source code snippets into gorgeous, shareable images for Twitter, LinkedIn, blog posts, and presentations with customizable gradient backgrounds and themes.
Open tool →
JavaScript Minifier
Compress, shrink, and minify JavaScript and ECMAScript code online. Strip whitespace and comments while preserving strings and regex literals for faster web page loads.
Open tool →
URL Slug Generator
Transform titles, headings, and product names into clean, SEO-friendly URL slugs with custom separators, stop word removal, and accent transliteration.
Open tool →
HTML Encoder / Decoder
Encode special characters into safe HTML entities or decode HTML entities back into plain readable text with support for named, decimal, and hex entities.
Open tool →
CSS Formatter & Beautifier
Format, beautify, and minify CSS code online. Clean up messy stylesheets, indent rules, sort CSS properties alphabetically, and compress stylesheet files client-side.
Open tool →
JavaScript Formatter & Beautifier
Format, beautify, and minify JavaScript and TypeScript code online. Clean up indentation, standardize semicolons and quotes, and compress scripts 100% in your browser.
Open tool →
Base64 Encode & Decode
Encode and decode Base64 text and binary data online with UTF-8 character support, URL-safe Base64, and instant clipboard copying 100% in your browser.
Open tool →
JSON to YAML / YAML to JSON Converter
Convert JSON to YAML and YAML to JSON online. Fast bi-directional serialization with indentation control, syntax error checking, and zero server uploads.
Open tool →
JSON to CSV / CSV to JSON Converter
Convert JSON to CSV and CSV to JSON online. Transform array records into spreadsheet-compatible CSV tables with delimiter options, nested object flattening, and instant download.
Open tool →
XML Formatter & Beautifier
Format, beautify, and minify XML, SOAP, SVG, and RSS documents online. Fix tag indentation, format XML trees, compress markup, and validate syntax 100% in your browser.
Open tool →
JWT Debugger & Decoder
Decode, inspect, and verify JSON Web Tokens (JWT) online. View claims, expiration dates, signature verification, and build tokens safely 100% in your browser.
Open tool →
cURL to Code Converter
Convert cURL command lines into production-ready code snippets for JavaScript Fetch, Axios, Python Requests, Go net/http, PHP cURL, and Node.js.
Open tool →
SQL Formatter & Beautifier
Format, beautify, and minify SQL queries online. Standardize uppercase keywords, indent joins and subqueries, and clean syntax client-side with zero data sent to external servers.
Open tool →
JSON Diff & Compare Online
Compare two JSON structures side-by-side with automatic key sorting, colored difference highlights, and change breakdown.
Open tool →
HTML Formatter & Beautifier
Format, beautify, and minify HTML, XML, and SVG markup with clean indentation, comment stripping, and real-time live preview.
Open tool →
Cronjob Explainer & Generator
Translate crontab schedule expressions into human-readable English, preview upcoming execution dates, and generate cron expressions interactively.
Open tool →
Regex Tester & Debugger Online
Test, evaluate, and debug regular expressions in real-time with visual match highlights, capture group inspection, and quick regex cheat sheets.
Open tool →
Markdown Preview & Editor
Live preview, edit, and convert Markdown (.md) documents online. Supports GitHub Flavored Markdown (GFM), tables, task lists, code blocks, HTML export, and real-time word counting.
Open tool →
About Developer Tools tools
UsefulGo developer tools provide fast, client-side utilities to inspect, format, validate, and debug code snippets and data structures without sending sensitive data to external servers.
Frequently asked questions
Do these developer tools upload my code or JSON to any server?
No. All developer tools run 100% locally in your web browser. Your JSON payloads, HTML source code, cron expressions, and regex test strings never leave your machine.
Can the JSON Formatter handle large files?
Yes, the JSON Formatter processes multi-megabyte payloads in memory right inside your browser without network latency or upload size limits.
Which cron formats are supported by Cronjob Explainer?
The explainer supports both standard 5-field cron syntax (minute, hour, day-of-month, month, day-of-week) as well as 6-field syntax including seconds.