API businesses thrive when they wrap a messy, fragmented data source or a complex workflow behind a clean endpoint. StartSeed generates ideas scoped to one data problem, one developer audience and one pricing tier.
A company-registration lookup API that returns structured data from 30+ national business registries in one JSON response. Free tier with 100 requests/month, then $0.01 per call. It could be called Registo.
A currency-hedging quotes API for e-commerce platforms that returns real-time forward rates and suggested hedge sizes. Charges $99/month per merchant. It could be called Hedgely.
A parcel-pickup points API that aggregates locker and store locations across 15 European carriers, with live availability. Pay-per-use at $0.002 per lookup. It could be called Pickupo.
Before shipping, publish a free tier with rate limits. If developers hit the ceiling and upgrade, you have product-market fit.
A data source or workflow that's painful to access directly, a developer audience that already pays for alternatives, and a pricing model that scales with usage.
Not for v1. Ship the endpoint, publish docs and a free tier. Add billing and analytics only after developers ask for it.