Where’s the lift?

Which fix moves the number most?

You have one sprint. Should the team work on the signup page or the onboarding? Funnel math tells you which change is worth more before anyone writes a line of copy.

The move

If one stage’s rate changes from a to b, the output gets multiplied by b ÷ a, no matter where in the funnel that stage sits. Compare fixes by their relative lift, not their point lift.

Worked example

Option A: signup 2% → 3%. Option B: activation 40% → 50%.

  1. A: 3 ÷ 2 = × 1.5 (+50%)
  2. B: 50 ÷ 40 = × 1.25 (+25%)
  3. A wins, even though it’s only +1 point vs +10 points
  • Small rates have the most room to grow in relative terms.
  • Two improvements stack by multiplying: × 1.5 and × 1.2 = × 1.8.