Sales Funnel Conversion Rate Calculator
Enter your stage-by-stage counts and get instant conversion rates, drop-off percentages, and a clear flag on which stage is quietly killing your funnel.
What's inside
- Stage conversion and drop-off rate formulas
- Overall funnel conversion rate formula
- Fully worked example across a 6-stage funnel
- Benchmark conversion ranges by stage type
- "Biggest leak" detection rule — benchmark gap, not raw lowest number
- Blank fill-in calculator table for your own stage counts
- Diagnostic questions to run once the leak stage is identified
Purpose: Most funnels don't have one problem — they have one stage that's much worse than the others, hiding behind an average that still looks acceptable. This calculator finds that stage.
How it works
For each stage, you need only the count of records that entered that stage in the period you're measuring.
Stage Conversion Rate = (# entering Stage N+1) ÷ (# entering Stage N) × 100
Drop-off Rate = 100% − Stage Conversion Rate
Overall Funnel Conversion Rate = (# reaching final stage) ÷ (# entering first stage) × 100
Worked example
| Stage | Count Entered | Conversion to Next Stage | Drop-off |
|---|---|---|---|
| 1. Leads | 1,000 | 300 ÷ 1,000 = 30% | 70% |
| 2. Marketing Qualified Lead (MQL) | 300 | 180 ÷ 300 = 60% | 40% |
| 3. Sales Qualified Lead (SQL) / Opportunity | 180 | 90 ÷ 180 = 50% | 50% |
| 4. Proposal / Demo | 90 | 54 ÷ 90 = 60% | 40% |
| 5. Negotiation | 54 | 36 ÷ 54 = 67% | 33% |
| 6. Closed Won | 36 | — | — |
Overall Funnel Conversion Rate = 36 ÷ 1,000 = 3.6%
Find the biggest leak
Compare each stage's conversion rate against a benchmark range (adjust for your industry/deal size — these are general B2B starting points):
| Stage transition | Typical healthy range | This funnel |
|---|---|---|
| Lead → MQL | 20–35% | 30% (healthy) |
| MQL → SQL/Opportunity | 50–65% | 60% (healthy) |
| Opportunity → Proposal | 55–70% | 50% (below range — flag) |
| Proposal → Negotiation | 55–70% | 67% (healthy) |
| Negotiation → Closed Won | 60–75% | 67% (healthy) |
Rule: The stage furthest below its benchmark range — even if not the lowest raw percentage — is your biggest leak, because it's underperforming relative to what's achievable at that stage. In the example above, Opportunity → Proposal at 50% (vs. a 55–70% benchmark) is the flagged leak, not Lead→MQL, even though 30% is a lower raw number — 30% is within its normal range for a top-of-funnel stage.
Blank calculator — fill in your own numbers
| Stage | Count Entered | Conversion to Next Stage (%) | Drop-off (%) | Vs. Benchmark |
|---|---|---|---|---|
| 1. | ||||
| 2. | ||||
| 3. | ||||
| 4. | ||||
| 5. | ||||
| 6. Closed Won | — | — | — |
Overall Funnel Conversion Rate = ______ ÷ ______ = ______%
Diagnostic questions once you've found the leak stage
- Is this a qualification problem (too many unqualified records entering the stage) or a conversion problem (qualified records stalling)?
- Has the conversion rate at this stage changed over the last 3 periods, or has it always been low? A recent drop points to a process/messaging change; a chronic low points to a structural funnel design issue.
- Is one rep or one segment dragging down the average at this stage, or is it uniform across the team?
How to use it
Pull your own stage counts for the last full period into the blank table, calculate each conversion rate, and compare against the benchmark ranges to find which single stage is underperforming relative to what's achievable — that's where to focus first, not the stage with the lowest raw number.