Developer Tools

A curated set of free, browser-based utilities for software engineers. Every tool runs client-side — your data never leaves your device. Built by a fintech engineer with deep context in payment systems, encoding, and cryptography.

Encoding & Decoding

JSON Formatter & Validator

Format, validate, and minify JSON in your browser.

Base64 Encoder / Decoder

Encode and decode Base64 text and files instantly.

URL Encoder / Decoder

Encode and decode URLs and query parameters instantly.

JSON ↔ YAML Converter

Convert between JSON and YAML instantly.

Auth & Security

Decode and inspect JWT tokens — header, payload, expiry.

Cryptography

Generate MD5, SHA-1, SHA-256, SHA-512 hashes of text or files.

Compute HMAC-SHA1/256/384/512 with payment-switch examples.

Generators

Generate UUIDs v1, v4, v7 — single or bulk.

Lorem Ipsum Generator

Generate placeholder text — words, sentences, or paragraphs.

Utilities

Cron Expression Builder

Build, parse, and explain cron expressions visually.

Test regular expressions with live match highlighting.

Markdown to HTML

Convert Markdown to HTML with live preview.

Banking & Payments

ISO 8583 Message Parser

Decode ISO 8583 hex messages field by field.

Design

Color Picker & Palette

Convert colors between HEX, RGB, HSL, OKLCH and build palettes.