Ostfold
- 🏢 Administrative centre: Sarpsborg
- 📏 Area: 4,181 km² (incl. lakes & islands)
- ⛰️ Highest point: Viktjernhøgda (331 m)
- 🕓 Time zone: CET / CEST (UTC +1 / +2)
- 💰 Currency: Norwegian krone (NOK)
- 💼 Main industries: Agriculture (grain), food processing, manufacturing (cellulose/paper & chemicals), logistics & ports, maritime
- 👥 Population: 314,407
- 🏙️ Municipalities: 12
- 🌊 Coastline: 382 km (Oslofjord / Skagerrak)
- 🗣️ Official language(s): Norwegian (Bokmål)
- 🏙️ Largest cities/towns: Fredrikstad, Sarpsborg, Moss, Halden