Sales Funnel Calculator

How the funnel math works

Each stage multiplies the one before it. Leads × lead-to-MQL rate gives MQLs, MQLs × MQL-to-SQL gives SQLs, SQLs × win rate gives customers, and customers × average deal value gives revenue. Because the stages multiply rather than add, the end number is far more sensitive to the rates than to the volume at the top: 1,000 leads through 30/40/25% rates produce 30 customers, while the same 1,000 leads through 40/50/30% produce 60.

Which conversion rate to fix first

Multiplication has a counter-intuitive consequence: a given relative improvement produces the same revenue gain at any stage. Lifting any one rate by a tenth lifts revenue by a tenth, whether it is the first stage or the last. So the stage worth attacking is not the one with the biggest theoretical impact — they are equal — it is the one where that relative gain is cheapest to get.

In practice that is usually the lowest-performing stage, because weak rates tend to have obvious causes: unqualified lead sources, a handover that drops leads, or a proposal step with no follow-up. Model each rate here one at a time and the cheapest point of leverage tends to become obvious.