16 calculators • 16 available now
Pretty-print, minify, validate, and debug JSON with line-by-line error detection and size statistics.
AvailableDecode JSON Web Tokens (JWT) locally, inspect Header & Payload claims, and check expiration status instantly.
AvailableEncode and decode Base64 text and binary data with full UTF-8 Unicode and URL-safe support.
AvailableTest, build, and debug regular expressions in real time with live match highlighting, group extraction, and cheat sheet.
AvailableConvert Unix epoch timestamps to human-readable UTC/local date-time strings and vice versa.
AvailableGenerate cryptographically secure UUID v4, v1, and v7 identifiers in bulk with custom formatting options.
AvailableGenerate cryptographically secure passwords and passphrases with custom character sets and entropy scoring.
AvailableGenerate MD5, SHA-1, SHA-256, SHA-384, and SHA-512 cryptographic hashes for text or files locally.
AvailableEncode and decode URLs according to RFC 3986 with URI component vs full URL modes and query string parser.
AvailableConvert color values between HEX, RGB, RGBA, HSL, HSV, and CMYK with visual preview and contrast ratio checker.
AvailableBuild, validate, and parse cron expressions visually with human-readable English descriptions.
AvailableLive side-by-side GitHub Flavored Markdown (GFM) editor and HTML renderer with export.
AvailableCompare two text blocks and highlight line-by-line insertions, deletions, and modifications.
AvailableMinify HTML, CSS, and JavaScript client-side to decrease payload size and speed up page loads.
AvailableGenerate customizable placeholder text by words, sentences, or paragraphs with HTML tag wrapping.
AvailableGenerate downloadable PNG and SVG QR codes for URLs, Wi-Fi credentials, contacts, and text locally.
AvailableDeveloper tools are essential browser-based utilities for software engineers, web developers, DevOps engineers, and UI designers. Working with JSON, JWTs, Base64 strings, regex patterns, timestamps, hashes, and UUIDs is part of every developer's daily workflow.
Our Developer Tools suite provides fast, 100% private, client-side tools that run entirely in your browser. None of your data, code, tokens, or hashes are ever sent to a server.
Security and privacy are non-negotiable when handling JWT access tokens, passwords, and sensitive API payloads. Third-party web tools that log inputs to remote servers present significant security risks. With ProCalc, all operations use native browser APIs (Web Crypto API, Canvas, RegExp, TextEncoder) — ensuring absolute privacy and zero-latency performance.
JSON Formatter & Validator, JWT Decoder & Expiration Inspector, Base64 Text & File Encoder/Decoder, Regex Live Tester with Match Explanations, Unix Timestamp & Date Converter, RFC-compliant UUID Generator (v1, v4, v7), CSPRNG Password Generator with Entropy Metrics, and Web Crypto Hash Generator (SHA-1, SHA-256, SHA-512, MD5).
Frontend & backend engineers, DevOps specialists, QA testers, security researchers, and students. Instant, zero-friction, serverless developer tools built for maximum daily utility.