Developer, AI & Web3 Tools

Create professional invoices with your logo, line items, taxes (GST/HST) and download a PDF. Save your company and invoice history in your browser. 100% free.

Format, validate, beautify and minify JSON online. Free, fast and fully in your browser.

Encode text to Base64 or decode Base64 to text instantly in your browser.

Decode a JSON Web Token (JWT) to inspect its header and payload. Nothing leaves your browser.

Encode or decode URL components (percent-encoding) right in your browser.

Generate random UUID v4 identifiers in bulk. Cryptographically secure, in your browser.

Generate SHA-1, SHA-256, SHA-384 and SHA-512 hashes from text using the Web Crypto API.

Convert Unix epoch timestamps to human-readable dates and back, in any direction.

Test JavaScript regular expressions against text and see matches and groups live.

Estimate how many tokens a prompt uses for LLMs like GPT and Claude, plus words and characters.

Generate a JSON Schema from a sample JSON object — handy for LLM tool/function definitions.

Convert between Wei, Gwei and Ether for Ethereum and EVM chains. Precise big-number math.

Compute the Keccak-256 hash of any text — the hashing used across Ethereum and Solidity.

Convert an Ethereum address to its EIP-55 checksummed form and validate it.

Count words, characters, sentences and paragraphs, with estimated reading time.

Convert text to UPPERCASE, lowercase, Title Case, camelCase, snake_case and kebab-case.

Turn any text or title into a clean, URL-friendly slug. Handles accents and symbols.

Generate placeholder Lorem Ipsum paragraphs, sentences or words for mockups and layouts.

Generate strong, random passwords with configurable length and character sets. Secure by Web Crypto.

Convert colors between HEX, RGB and HSL and preview them live.

Generate a QR code from any text or URL and download it. Free and in your browser.