Quick learn
A fictional company is sizing a home-router maintenance service in a metro. It estimates 400,000 eligible broadband households, 25% with a relevant need, and one purchase annually at ₹800.
Deep dive
Define the geography, buyer, period and unit before calculating. Build a range around uncertain inputs. Keep total potential demand separate from the homes you can reach and serve in the first year.
Worked decision
400,000 × 25% × 1 × ₹800 = ₹8 crore in annual potential demand under these assumptions. If service coverage reaches 20% of eligible homes, reachable demand is ₹1.6 crore before adoption.
When the decision changes
TRAI counted roughly 1.259 billion wireless subscriptions at December 2025, including mobile connections and fixed wireless access. That count is a context check, not a count of unique metro broadband households. Validate the 25% need assumption locally.