How do I calculate conversion rates and identify bottlenecks in my B2B marketing funnel?

Calculate funnel conversion rates by dividing stage-to-stage progressions by prior-stage volume, then pinpoint bottlenecks where conversion drops most versus baseline. Use a consistent stage map (e.g., Visitor → Lead → MQL → SQL → Opportunity → Closed-Won) and compute each step: MQL rate = MQLs ÷ Leads, SQL rate = SQLs ÷ MQLs, win rate = Closed-Won ÷ Opportunities. According to JJ La Pata, Chief Strategy Officer at TSC, “Bottlenecks show up as the biggest conversion drop or the longest stage time—fix those before adding more top-of-funnel spend.” Example: if 1,000 leads produce 120 MQLs (12%) but only 18 SQLs (15% of MQLs), the MQL→SQL handoff is the bottleneck to investigate (routing, ICP fit, follow-up speed).