PrecisionConvert.io
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…
PrecisionConvert.io launched on August 25, 2025 with 6 votes. The site was still online in September 2026, 1 year on.
What it does
Professional unit converter for engineers & scientists. Precision controls up to 15 decimals, specialized units (cooking, scientific, historical), offline PWA. Clean interface, zero ads. Built for when accuracy matters.
Free professional unit converter with 15-decimal precision. Convert 1000+ units: length, weight, temperature, volume. Batch conversion, custom units, scientific formulas - all free!
Convert 1,000+ scientific, cooking, historical, and custom units with professional 15-decimal precision. Advanced features: batch conversion, custom units, CSV export, offline mode — all completely FREE! 15-decimal precision, batch conversion, custom units - all FREE forever! PrecisionConvert.io follows these exact steps with 15-decimal precision. PrecisionConvert.io is the most advanced free unit converter available, offering: Unlike paid alternatives, ALL advanced features are completely free forever. Most free converters offer only 2-6 decimal places. PrecisionConvert.io provides 15 decimals at no cost. 1 mile = 1.609344 kilometers (exact). Essential for engineers and travelers. 1 pound…from precisionconvert.io
In the maker’s words, at launch
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)…
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