GDU Tracker

GDU Calculator is the field-ready Growing Degree Unit tracker built for farmers
and agronomists. Set up your fields, enter a planting date, and the app
automatically pulls historical and forecast weather to calculate accumulated GDUs
and show you exactly where your crop stands in its growth cycle.

🌱 SUPPORTED CROPS
Corn, Soybean, Wheat, Barley, Oats, Canola, Flax, Sunflower, Field Peas, Dry
Beans, Sugar Beet, Potato, Alfalfa, Cool-Season Grass — and fully customizable
crops with your own base temperature and growth stages.

📊 WHAT IT DOES
• Accumulates GDUs from planting date using historical weather data
• Projects forward with a 7-day forecast so you can plan ahead
• Shows key growth stages (emergence, silking, maturity, etc.) on a live chart
• Supports multiple GDU calculation methods: Simple, Modified (corn), and Capped
• Tracks field operations — planting, herbicide, fungicide, fertilizer,
irrigation, scouting, harvest, and more — plotted right on your GDU chart
• Manages multiple fields, each with its own crop, planting date, and location

🗺️ LOCATION & WEATHER
Set a field location by searching a place name or tapping "Use My Location" for
GPS. Weather is fetched automatically from Open-Meteo's free weather API.
Optionally connect your own Ambient Weather Network (AWN) station for
hyperlocal, on-farm data.

📁 YOUR DATA, YOUR DEVICE
No account. No sign-up. All field data is stored locally on your device. Export
any field — or your entire farm — to a JSON file for backup or transfer. Import
it on another device in seconds.

✅ DESIGNED FOR THE FIELD
• Works offline once weather data is loaded
• Dark mode support
• Fahrenheit / Celsius toggle
• Clean, fast interface built for quick daily checks

Whether you're timing a fungicide pass, watching for silk emergence, or planning
harvest logistics, GDU Calculator gives you the numbers you need — right when
you need them.