5 filters → realistic addressable count, broken down by vertical and geography. Tells you when your ICP is too small to sustain outbound at the volume you need. Cross-references with the Volume Calculator to flag ICP-volume mismatches.
How accurate is this? These are educated estimates from Apollo / Crunchbase / LinkedIn data + B2B census aggregates — directionally correct but easily ±30%. The point is to spot order-of-magnitude problems (e.g. "your TAM is 200 companies and you want to send 5K/mo"), not to be a precise list builder. Validate by actually building a sample list in Apollo / Clay.
