Free Online Developer Tools — JSON, Base64, URL & More

Essential utilities for developers and engineers. Instant results, no backend, completely private.

About These Developer Tools

Modern software development requires constant interaction with data formats, encodings, and identifiers that aren't always human-readable. Developer tools bridge the gap between raw machine data and the formats humans can actually understand and debug. Whether you're troubleshooting an API response, encoding a file for transmission, or generating a unique ID for a database record, having the right utility at your fingertips saves time and prevents errors.

JSON (JavaScript Object Notation) is the lingua franca of web APIs and configuration files. When you receive a compressed, minified JSON string from an API response, reading it without formatting is nearly impossible. A JSON formatter instantly structures that data into an indented, color-coded tree that reveals the exact shape of the payload. It also validates the JSON syntax, highlighting any errors so you can fix them before they cause bugs in production code.

Base64 encoding is used extensively in web development for embedding binary data — such as images, fonts, or files — directly in HTML, CSS, or JSON. It's also used in HTTP Basic Authentication headers and in encoding email attachments. Our Base64 encoder and decoder lets you instantly convert between raw text or binary data and its Base64 representation, with support for both standard and URL-safe alphabets.

URL encoding (also called percent-encoding) ensures that special characters in URLs — spaces, ampersands, equal signs — are safely transmitted over the internet without being misinterpreted by servers and browsers. Our URL encoder/decoder handles both full URL encoding and component encoding, so query strings and path segments are always correctly formatted.

UUIDs (Universally Unique Identifiers) are 128-bit values used to uniquely identify records in databases, sessions, API keys, and distributed systems. Generating a UUID v4 requires a cryptographically random source to guarantee uniqueness. Our UUID generator uses the browser's built-in crypto API to produce RFC 4122-compliant UUIDs instantly.

Developer Tools

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JSON Formatter

Format, validate and minify JSON data with syntax highlighting and error detection.

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Base64 Encoder / Decoder

Encode text or files to Base64 and decode Base64 strings back to readable content.

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URL Encoder / Decoder

Encode and decode URLs online. Handle special characters and query strings safely.

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UUID Generator

Generate UUID v4, random strings and unique identifiers using the browser's crypto API.

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Color Picker

Pick colors and convert between HEX, RGB, and HSL formats for use in CSS or design.

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