Free Developer Tools That Just Work

No signup, no tracking, no server calls. Everything runs in your browser — fast, private, and always available.

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Regex Tester

Test, debug, and validate regular expressions with real-time matching, group capture, and syntax highlighting.
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JSON Formatter

Beautify, minify, validate, and tree-view JSON data. Detect errors with line numbers and fix them instantly.
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Base64 Encode/Decode

Encode text or files to Base64 and decode back. Supports URL-safe Base64 and automatic detection.
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Hash Calculator

Calculate MD5, SHA-1, SHA-256, SHA-384, and SHA-512 hashes instantly using the Web Crypto API.
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UUID Generator

Generate RFC 4122 v4 UUIDs in bulk. Copy one or all. Fast, cryptographic, standards-compliant.
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URL Encoder/Decoder

Encode and decode URLs, query parameters, and form data. Handles full strings or component encoding.
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Color Converter

Convert between HEX, RGB, HSL, and CSS named colors. Live preview with copy support for every format.
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HTML Entity Encoder

Encode special characters to HTML entities and decode them back. Supports named, decimal, and hex entities.
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Timestamp Converter

Convert Unix timestamps to human-readable dates and vice versa. Supports seconds and milliseconds.
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JWT Decoder

Decode JSON Web Tokens to inspect header, payload, and claims. Detects expiration and algorithm type.
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Markdown Previewer

Write Markdown and see the rendered HTML in real-time. Supports tables, code blocks, and links.
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CSS Gradient Generator

Create linear and radial gradients with multiple color stops, live preview, and copy-ready CSS code.
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Number Base Converter

Convert numbers between binary, octal, decimal, hex, and any base from 2 to 36.
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Cron Expression Parser

Decode cron expressions into human-readable schedules with next run times.
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Diff Checker

Compare two texts side by side and see added, removed, and changed lines highlighted.

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