Conversion compounds across the funnel.
Each conversion rate applies only to the people or opportunities that reached the preceding stage. Multiplying the three rates gives the complete lead-to-win probability. The forward model shows how a starting cohort progresses; the reverse model estimates the lead volume associated with a target number of expected wins.
Stage labels are a planning convention, not a universal sales process. Use one cohort and allow enough time for it to complete the funnel. Multiplying unrelated weekly activity totals can double-count people or confuse stage aging with conversion. Expected counts can be fractional; whole leads are rounded only at the final sourcing requirement.
The formula, made clear.
- Conditional conversion
- Each rate uses the immediately preceding stage as its denominator.
- Expected counts
- Fractional mathematical expectations, not guaranteed customer counts.
- Whole leads to source
- Ceiling of the unrounded lead requirement; intermediate stages are not rounded.
Put the numbers in context.
At 20%, 50% and 25% conditional conversion, 10,000 leads become 2,000 qualified opportunities, 1,000 sales opportunities and 250 expected wins. A 100-win target requires 4,000 leads at those rates.
| Input | Example value |
|---|---|
| Starting leads | 10,000 leads |
| Leads → qualified opportunities | 20% |
| Qualified → sales opportunities | 50% |
| Sales opportunities → closed-won | 25% |
| Target closed-won customers | 100 customers |
| Required leads for expected target wins | 4,000 |
What this calculation assumes
One cohort with no re-entry, duplicate leads, differing segments or time-varying conversion. Every rate is conditional on the previous stage. No elapsed-time or cash forecast. A zero stage rate cannot support positive target wins; zero target requires zero leads.
What to consider next.
Compare the reverse requirement with lead-generation capacity and cost. Use a compatible opportunity stage when connecting this model to pipeline coverage.
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