Show HN: Precisionconvert.io – Professional unit converter for engineers

I built this after getting frustrated with existing converters that are either ad-heavy or lack precision controls. Designed specifically for professionals who need accuracy in their calculations.

Key technical decisions: - Single HTML file for fast loading and offline capability - Vanilla JavaScript (no frameworks) for maximum performance - PWA implementation for mobile/desktop use - Precision controls up to 15 decimal places - Specialized units for cooking, scientific, and historical conversions

Built it in 24 hours using Claude Code and deployed on Netlify. The challenge was balancing simplicity with professional features that justify premium pricing.

Tech stack: HTML5/CSS3/JS, Stripe for payments, Netlify Functions for backend processing.

Would love feedback on the technical approach and the specialized unit categories. What units would be most valuable for your work?

Happy to answer questions about the rapid development process or specific implementation details.