TAM, SAM and SOM are three nested estimates of market size. Total addressable market is every company that could use the product; serviceable addressable market is the part your business model, geography and channel can reach; serviceable obtainable market is the share you can realistically win in a planning period. Lead databases supply the company counts behind SAM. Apply a reachability discount to any count that comes from contact data: in 2026, only about a third of business addresses on typical lists confirmed valid.
Top-down estimates start from industry totals and apply percentages; bottom-up estimates count companies matching the profile in a database and multiply by expected revenue per account. Bottom-up is more defensible and depends on the database's coverage and the filter quality.
The ideal customer profile is the filter that turns TAM into SAM. For SOM, the honest input is the number of accounts you can reach and work in the period, which is a function of verified contacts and rep capacity rather than market size.
A verification vendor counts 310,000 companies worldwide that send email at volume (TAM). Its model serves English, French and Spanish speaking SMBs and agencies: 95,000 (SAM). Two reps can work 4,000 verified accounts a year at a 3% close rate: 120 new customers, which, times revenue per account, is the SOM for the year.
Verify a list or a single address. 100 free checks a month, unknowns refunded.
Verify Leads - FreeAyoub built BounceZero's 5-stage validation pipeline, its dedicated BGP-announced IP infrastructure, and the Patroni HA PostgreSQL cluster behind every verification. Previously built high-volume email delivery infrastructure. Trained at 1337 Benguerir (École 42 network, 2019). Open-source: bgp_analyzer.