Sample Size Calculator

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Lift (that can be detected with power (80%) probability) 5%10%
Absolute Difference in Conversion Rate (that can be detected with power (80%) probability) 0.59%1.18% 2.07%
Conversion Rate of Alternative (that can be detected with power (80%) probability) 12.39%12.98% 13.87%
Sample Size per Offer (# of visitors) 47,94212,234 4,114
Sample Size per Offer (# of conversions) 5,6571,444 485
Days to Complete Test 247 3
Weeks to Complete Test 41 1