Developer tools that run locally.
Fast, private, free utilities for debugging, transforming, and inspecting code. Formatted, decoded, and executed strictly inside your browser.
Essential Developer Utilities
JSON Formatter & Validator
Format, indent, validate and inspect JSON with syntax error location and tree view.
JSON Diff Checker
Compare two JSON payloads side-by-side with structural diffing and key sorting.
JSON to CSV & CSV to JSON Converter
Convert JSON arrays to CSV spreadsheets and CSV back to JSON with live table preview.
Base64 Encoder & Decoder
Encode and decode text, hex, URL-safe Base64, and convert images/files to Data URIs.
JWT Decoder & Inspector
Decode and inspect JSON Web Tokens (Header, Payload, Claims, Expiration) with client-side verification.
Regex Tester & Explainer
Test regular expressions with real-time match highlighting, capture groups, and token explanation.
JSON Formatter & Validator
Format, indent, validate and inspect JSON with syntax error location and tree view.
JSON Diff Checker
Compare two JSON payloads side-by-side with structural diffing and key sorting.
JSON to CSV & CSV to JSON Converter
Convert JSON arrays to CSV spreadsheets and CSV back to JSON with live table preview.
JSONPath & Schema Validator
Test JSONPath query expressions and validate JSON against JSON Schema definitions.
Base64 Encoder & Decoder
Encode and decode text, hex, URL-safe Base64, and convert images/files to Data URIs.
JWT Decoder & Inspector
Decode and inspect JSON Web Tokens (Header, Payload, Claims, Expiration) with client-side verification.
URL Encoder & Decoder
Encode and decode URLs, query parameters, and reserved characters with RFC 3986 compliance.
Cryptographic Hash & Checksum Generator
Generate SHA-256, SHA-512, SHA-1, MD5, and HMAC hashes locally using Web Crypto API.
HTML Entity Encoder & Decoder
Encode special characters into HTML entities and decode HTML entities to plain text.
Regex Tester & Explainer
Test regular expressions with real-time match highlighting, capture groups, and token explanation.
Text & Code Diff Checker
Compare text and code line-by-line or character-by-character with visual side-by-side diffing.
SQL Formatter & Beautifier
Beautify, indent, format, and minify SQL queries across PostgreSQL, MySQL, and SQLite dialects.
Cron Expression Parser & Humanizer
Translate cron expressions into human-readable English and calculate upcoming execution schedules.
Unix Timestamp & Epoch Converter
Convert Unix epoch timestamps to human-readable dates, UTC, ISO 8601, and local time with live ticker.
UUID & Random ID Generator
Generate cryptographically secure UUID v4, UUID v7 style, NanoIDs, and bulk unique identifiers.
Live Markdown Editor & Preview
Edit markdown with real-time split-screen preview, HTML export, word counters, and cheatsheet.
CSS Gradient Generator
Design linear, radial, and conic CSS gradients with multi-color stops and Tailwind code export.
Color Converter & WCAG Contrast Checker
Convert HEX, RGB, HSL, and HSV colors and evaluate WCAG 2.1 AA/AAA accessibility contrast ratios.
CSS Box Shadow & Glassmorphism Generator
Design layered shadows, smooth glows, and glassmorphic card effects with live preview and code export.
HTML to JSX & React Converter
Convert raw HTML markup and inline styles into clean React JSX components with camelCase attributes.
SVG Viewer, Optimizer & Data URI Converter
Clean up SVGs, remove metadata, convert to React components, and generate CSS Data URIs.
URL & Query Parameter Parser / Builder
Deconstruct URLs into protocol, host, path, and interactively build, edit, and toggle query parameters.
cURL to Fetch, Axios & Python Converter
Convert cURL terminal commands into JavaScript fetch, Axios, and Python requests code.
HTTP Status Code Lookup & Guide
Searchable directory of HTTP status codes with RFC specifications, causes, and debugging tips.
User-Agent Parser & Device Inspector
Inspect your current client device specifications or parse any custom User-Agent string.
Browse by Category Hub
JSON & Data
Format, validate, compare and transform structured data
Encoding & Crypto
Decode tokens, convert encodings and compute local hashes
Code & Debugging
Analyze expressions, compare diffs and test timestamps
Web & CSS Styling
Generate modern CSS, gradients, colors and convert JSX
API & Network
Parse URLs, inspect headers, convert cURL and check status
Local-First Browser Architecture
When inspecting JSON payloads, testing regular expressions, or decoding JWT tokens, developers handle confidential payloads. All operations execute strictly within local V8 JavaScript memory.
Zero Server Uploads
All parsing, transformation, and formatting operations execute in local V8 JavaScript memory.
Hardware Accelerated
Hashes and crypto calculations utilize the W3C Web Cryptography API (`crypto.subtle`) for native CPU speed.
Zero Data Uploads
No login walls, zero server data uploads, no advertisements, and no rate limits. Your code stays strictly in your browser.