Free Online Developer Tools

Fast, private, browser-based. No sign-up required. Works offline.

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JSON Formatter

Prettify, minify, and validate JSON instantly in your browser.

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Base64 Encode / Decode

Encode text to Base64 or decode Base64 back to plain text.

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UUID Generator

Generate v4 UUIDs instantly — single or batch.

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URL Encode / Decode

Encode or decode URL components and query strings.

 Aa

Text Case Converter

Convert text to UPPER, lower, Title, camelCase, snake_case, and more.

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Markdown Preview

Live Markdown editor with real-time HTML preview. Supports GFM tables, task lists, and code blocks.

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Color Converter

Convert colors between HEX, RGB, and HSL formats with a live color preview.

 .*

Regex Tester

Test regular expressions in real time with match highlighting and capture group details.

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Hash Generator

Generate MD5, SHA-1, SHA-256, SHA-384, and SHA-512 hashes from any text.

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Timestamp Converter

Convert Unix timestamps to human-readable dates and vice versa. Auto-detects seconds vs milliseconds.