47 Alternative Data Sources for Angel Investors in 2026

Most angel investors only check Crunchbase, LinkedIn, and the pitch deck. All three are lagging indicators. This guide covers 47 alternative data sources across 10 categories, each with an access note, typical lead time, and a starting URL. The categories cover public code signals, hiring, product telemetry, infrastructure buildouts, search and attention, funding precursors, community growth, regulatory filings, open-data scientific signals, and niche commercial APIs. Use this as a reference for building a sourcing stack that surfaces breakout companies 6-12 weeks before they hit a VC database.