Developer Tools
Format JSON, generate UUIDs, test regex, hash strings, encode Base64 and URLs — every tool runs entirely in your browser. Open DevTools → Network and watch: nothing leaves your tab.
Built for daily developer workflows
Eight tools for JSON, hashing, HMAC signing, regex, encoding and ID generation. Pages target Lighthouse 100 on mobile and load in under 100ms TTI.
Pick a tool below or jump straight to JSON Formatter if that's why you came.
JSON Formatter & Validator
Format, validate, and minify JSON with syntax highlighting and tree view.
UUID Generator
Generate UUID v4 instantly. Bulk generate, copy with one click.
Base64 Encoder / Decoder
Encode or decode Base64 strings instantly. Supports text and file input.
URL Encoder / Decoder
Encode or decode URLs and query strings. Handles Unicode and percent-encoding.
Regex Tester
Test regular expressions with live matching, pattern explainer (token-by-token), and replace.
Hash Generator
Generate MD5, SHA-1, SHA-256, SHA-384, SHA-512 hashes from any text or file. Hex or Base64 (SRI ready).
HMAC Generator
Sign payloads with HMAC-SHA-256 / SHA-512 (and MD5/SHA-1 for legacy). Stripe, GitHub, Slack, Twilio webhooks & JWT.
Markdown Preview
Write and preview Markdown in real-time. Side-by-side editor with live rendering.
Frequently Asked Questions
Why no built-in API or CLI to use these tools programmatically?
These tools are 100% client-side and designed for interactive use. A public API (api.praticulus.com/v1) and an npm CLI (@praticulus/cli) are planned for automated workflows — see Coming next.
Can these tools handle very large inputs (10MB+ JSON)?
Yes, within the limits of your browser's RAM. Around 100 MB JSON parsing remains smooth on a modern machine. No application-side hard limit on Praticulus.
Are the regex, JSON and Base64 engines spec-compliant?
They use native browser APIs (JSON.parse, ECMAScript RegExp, atob/btoa, Web Crypto API for hashes). Behavior is identical to what your production JS runtime will produce.
Can I share a formatted result with a teammate via URL?
Not yet on every tool. URL sharing (state encoded in the hash fragment) is planned across 9 tools — see tool-engagement-url-state in the roadmap.
Where can I see the source code of the tools?
A public GitHub repo (iris-digital/praticulus, MIT license) is planned and will be linked in the footer at launch. In the meantime, View Source in your browser shows everything — all logic is inline.