Developer Tools that just work
Format JSON, decode JWT, test regex, generate UUIDs, and more. All tools run entirely in your browser — your data never leaves your device.
Popular Tools
The tools developers reach for every day.
JSON Formatter & Beautifier
Format and beautify JSON with proper indentation and syntax highlighting.
Base64 Encode / Decode
Encode text to Base64 or decode Base64 strings back to text.
JWT Decoder
Decode JSON Web Tokens and inspect header and payload.
Regex Tester
Test regular expressions with real-time matching and highlighting.
UUID Generator
Generate random UUIDs (v4) in bulk with one click.
Timestamp Converter
Convert Unix timestamps to human-readable dates and vice versa.
SQL Formatter & Beautifier
Format and beautify SQL queries with proper indentation and keyword highlighting.
Hash Generator
Generate MD5, SHA-1, SHA-256, and SHA-512 hashes from text.
Browse All Developer Tools
Filter by category and find exactly what you need.
JSON
Format, validate, minify, and convert JSON dataJSON Formatter & Beautifier
Format and beautify JSON with proper indentation and syntax highlighting.
JSON Validator
Validate JSON syntax with detailed error messages and line numbers.
JSON Minifier
Compress JSON by removing whitespace and unnecessary characters.
JSON to CSV Converter
Convert JSON arrays to CSV format for spreadsheet import.
JSON to XML Converter
Transform JSON data into XML format with proper element nesting.
JSON to YAML Converter
Convert JSON to human-readable YAML format.
JSON Diff
Compare two JSON objects side-by-side and highlight every difference.
JSON to TypeScript
Generate TypeScript interfaces and types from JSON objects instantly.
Large JSON Handler
Process and view large JSON files (100MB+) without freezing the browser using Web Workers.
XML
Format and structure XML documentsHTML
Format, minify, and encode HTMLCSS
Format and minify CSS stylesheetsJavaScript
Minify and beautify JavaScript codeSQL
Format and beautify SQL queriesEncoding
Encode and decode various formatsSecurity
Decode tokens and generate hashesUtilities
General-purpose developer utilitiesRegex Tester
Test regular expressions with real-time matching and highlighting.
UUID Generator
Generate random UUIDs (v4) in bulk with one click.
Timestamp Converter
Convert Unix timestamps to human-readable dates and vice versa.
YAML Formatter & Validator
Format, validate, and convert YAML with error reporting.
Cron Expression Generator
Build and validate cron expressions with a visual schedule builder.
Number Base Converter
Convert numbers between binary, decimal, hexadecimal, and octal formats.
cURL to Code Converter
Convert cURL commands to JavaScript, Python, Go, PHP, and other languages.
API Tester
Make HTTP requests, test REST endpoints, and view responses with this lightweight API testing tool.
Mock Data Generator
Generate realistic mock data in JSON, CSV, and SQL formats for testing and development.
Reference
Quick reference and lookup toolsWhy developers choose DevKit
Built by developers, for developers. Every detail is designed for speed, privacy, and productivity.
100% Client-Side
All processing happens in your browser. Your data is never uploaded to any server. Complete privacy, zero latency.
Lightning Fast
No server round-trips. Tools execute instantly on your machine.
No Signup Required
Just open and use. No accounts, no email verification, no tracking.
32 Tools in One Place
JSON, XML, HTML, CSS, Base64, JWT, Regex, UUID, Hash, Timestamp, and more. Stop switching between sites.
Dark Mode Default
Built for developers who prefer dark mode. Toggle to light mode anytime.
SEO-Optimized
Structured data, clean URLs, and fast load times. Find us when you search for any developer tool.
How It Works
Three steps. No friction. Just results.
Pick a Tool
Browse 32 developer tools organized by category. Find exactly what you need in seconds.
Paste Your Data
Paste or type your input directly into the tool. Everything stays in your browser — nothing is uploaded.
Get Instant Results
Results appear immediately as you type. Copy to clipboard with one click and get back to work.
Frequently Asked Questions
Everything you need to know about DevKit.
Yes, all 21 tools are 100% free with no signup required. We support the site through display ads, never by charging for tools or selling your data.
Absolutely. All tools run entirely in your browser using client-side JavaScript. Your data is never uploaded to any server. Nothing leaves your device.
No. Just open any tool and start using it immediately. No email, no password, no verification step.
Once a tool page is loaded, it works offline since all processing happens client-side. You can bookmark tools for quick access.
Our tools process data in the browser efficiently. For very large JSON files, formatting and validation work without freezing your tab.
All modern browsers including Chrome, Firefox, Safari, and Edge. The tools use standard web APIs that work everywhere.