Developer Tools

Free Online Tools - Developer & Utility Tools

Free online tools for developers. JSON formatter, password generator, color converter, regex tester, and 30+ more. No signup required.

How to Convert CSV to JSON Online Free

Learn how to convert CSV files to JSON format online for free. Step-by-step guide covering CSV format rules, common errors, and bulk conversion tips.

How to Decode a JWT Token (Without a Library)

Learn how to decode JWT tokens and understand their structure. Covers header, payload, signature, security tips, and common debugging techniques.

JavaScript Beautifier

Free JavaScript beautifier. Paste minified JS and get clean, formatted code with proper indentation. Choose 2-space, 4-space, or tab indent style.

Base64 Encoder & Decoder

Free Base64 encoder and decoder. Convert text to Base64 or decode Base64 strings instantly in your browser. Supports UTF-8 encoding and bulk input.

Chmod Calculator

Free chmod calculator for Unix file permissions. Toggle read, write, and execute for owner, group, and others to get the numeric chmod value instantly.

Crontab Expression Generator

Free crontab expression generator. Build cron schedules visually with human-readable descriptions and next run times. No signup required.

CSV to JSON Converter

Free CSV to JSON converter. Paste CSV data and get clean JSON output instantly. Auto-detects headers and data types. No signup or upload required.

Hash Generator (MD5, SHA-256, SHA-512)

Free hash generator for MD5, SHA-1, SHA-256, and SHA-512. Compute hashes from any text instantly in your browser. No data sent to any server.

How to Format JSON Online (Free, No Signup)

Learn how to format, validate, and beautify JSON data online for free. Step-by-step guide with examples for API debugging, config files, and data cleaning.

How to Test Regex Online (with Live Matching & Debugging)

Learn how to test and debug regular expressions online. Covers common regex patterns, flags, capture groups, and real-time match highlighting.

HTML Entity Encoder & Decoder

Free HTML entity encoder and decoder. Convert special characters to HTML entities or decode entities back to text instantly in your browser.

HTTP Status Codes Reference

Free HTTP status codes reference. Searchable list of all HTTP response codes with descriptions, explanations, and common usage examples for developers.

JSON Formatter & Validator

Free JSON formatter and validator. Paste messy JSON and instantly format, validate, and beautify it with syntax highlighting and error line numbers.

JSON to CSV Converter

Free JSON to CSV converter. Convert JSON arrays to downloadable CSV files. Handles nested objects and auto-detects field names. No signup required.

JSON to YAML Converter

Free JSON to YAML converter and vice versa. Paste JSON or YAML and get clean, readable output in the other format. Runs entirely in your browser.

JWT Token Decoder

Free JWT token decoder. Decode JSON Web Tokens and inspect the header, payload, and signature instantly. No data sent to any server. 100% private.

Markdown to HTML Preview

Free Markdown to HTML previewer. Write Markdown on the left and see rendered HTML in real time on the right. No signup, runs in your browser.

Regex Tester & Debugger

Free regex tester and debugger. Test regular expressions in real time with match highlighting, capture groups, and flag support. No signup needed.

Text Diff Checker

Free text diff checker. Compare two texts side by side with additions, deletions, and changes highlighted. Runs in your browser, no data uploaded.

Text to Binary Converter

Free text to binary converter. Convert text to binary code and binary back to text. Also supports HEX and octal conversions. No signup required.

Unix Timestamp Converter

Free Unix timestamp converter. Convert Unix epoch timestamps to human-readable dates and vice versa. Shows the current timestamp live. No signup needed.

URL Encoder & Decoder

Free URL encoder and decoder. Encode or decode URLs and query strings with full support for special characters and UTF-8. Runs in your browser.

UUID Generator (v4)

Free UUID v4 generator. Generate random UUIDs in bulk and copy one or many with a single click. No signup needed, runs entirely in your browser.

Best Claude Code Skills 2026 - Curated Directory of AI Coding Skills

Curated directory of the best Claude Code skills for development, security, SEO, and DevOps. 31,700+ skills organized by category.