Hey Product Hunt! 👋 I'm a solo developer, and I built GridConvertPro out of pure frustration. The problem: I constantly needed to convert coordinates between formats — lat/long ↔ UTM ↔ MGRS ↔ Plus Codes — and every tool I found was either cluttered with ads, hidden behind a paywall, or quietly sent my coordinates off to some server. For a simple math operation, that felt wrong. So I built a clean, fast converter that does everything in the browser: • All major formats, two-way conversion + a live interactive map • Distance, bearing & rhumb line (loxodrome) — handy for marine navigation • Magnetic declination (WMM-2020), solar times, elevation & area measurement • Bulk conversion, multi-waypoint routes and place search • Works offline as a PWA, no signup, completely free What started as a basic lat/long ↔ UTM converter kept growing as I asked "what would a surveyor, a sailor, or a drone pilot actually need?" — and that's how the marine, magnetic and solar tools came to life. The core math runs entirely client-side, so your coordinates never leave your device. I'd genuinely love feedback — especially from anyone in GIS, surveying, aviation, sailing or geocaching. What format or feature should I add next?

GridConvertPro

Convert GPS coordinates between every format, free ⭐

Convert GPS coordinates between every format, free ⭐