Free Online Developer Tools

Free online developer tools — JSON formatter, Base64 encoder, QR code generator, timestamp converter, and more. No sign-up required.

Developer Tools

JSON Formatter

Format, validate, and beautify JSON data instantly. Parse and fix malformed JSON with syntax highlighting.

Base64 Encoder / Decoder

Encode text to Base64 or decode Base64 strings back to plain text. Supports UTF-8 and binary data.

URL Encoder / Decoder

Encode special characters for URLs or decode percent-encoded URLs back to readable text.

Timestamp Converter

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

Markdown Previewer

Write and preview Markdown in real-time. See how your Markdown renders as HTML instantly.

Regex Tester

Test regular expressions against text with real-time matching. See matches, groups, and replacements.

UUID Generator

Generate random UUIDs (v4) and GUIDs. Copy with one click. Perfect for developer testing.

Hash Generator

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

JWT Decoder

Decode JWT tokens and inspect the header, payload, and signature. No data is sent to any server.

HTML Entity Encoder / Decoder

Encode special HTML characters to entities and decode HTML entities back to readable text.

Text Diff Checker

Compare two texts and find differences instantly. See what was added, removed, or changed line by line.

Text Tools

Word Counter

Count words, characters, sentences, and paragraphs. Get reading time estimates for your text.

Lorem Ipsum Generator

Generate Lorem Ipsum placeholder text for your designs. Customize paragraph count and length.

Text Deduplicator

Remove duplicate lines from text. Sort alphabetically, keep first occurrence, or remove all duplicates.

Case Converter

Convert text to uppercase, lowercase, title case, sentence case, camelCase, snake_case, and more.

Image Tools

Image Compressor

Compress JPEG, PNG, and WebP images online. Reduce file size without losing quality. 100% client-side.

Image to Base64

Convert images to Base64 data URIs. Embed images directly in HTML, CSS, or JSON without external files.

Utility Tools

QR Code Generator

Generate QR codes from URLs, text, or any data. Customizable size and color. Free, no sign-up needed.

Password Generator

Generate strong, secure passwords with customizable length, symbols, numbers, and case options.

Color Converter

Convert colors between HEX, RGB, HSL, and HSV formats. Pick colors visually with the color picker.