Creative Testing Duration Forecaster
Know how many days a creative test needs before you can trust the result.
$
$
~100+ for a stable read.
Test duration
40.0 days
To a sound sample
Finishes around
Aug 16
Don't call it before this
Conversions needed
300
Across all variants
Est. test cost
$12,000
Duration × daily spend
This test needs ~40 days — long enough that fatigue and seasonality creep in. Cut variants, raise budget, or lower the per-variant bar.
Rule of thumb: ~100 conversions per variant for a directional read, more for small lifts. Ending early is the most common testing mistake.
About this calculator
From daily spend, CPA, variant count and required conversions per variant, forecast the days a test needs to reach a sound sample — so you stop calling winners early.
Everything runs in your browser — nothing you type is sent anywhere or stored. Use it to sanity-check a plan, pressure-test a channel, or brief a team before you commit budget.