Series A is the first time professional VC funds — not just angels — write you a serious check. You've proven your product works. Now they're betting you can grow it into something massive. This is a different league. Series A investors are firms like Sequoia, a16z, and Benchmark. They invest millions and expect you to grow 3x–5x per year. Typical Series A round: $5M to $20M Typical valuation: $15M to $60M pre-money