free
Statistics & Experiments
Sample Size Lab
Design A/B proportion and continuous two-sample tests with power and alpha.
Runs in your browser by default — private, fast, and ready to export.
How to use, examples & FAQShowHide
How to use
- Choose test kind
- Set baseline and lift
- Export required n
Example
A/B conversion · baseline 10% · lift 10% · power 80%
Benefits
- Power/alpha controls
- Multiple test kinds
- Exportable brief
FAQ
Guarantees significance?
No. It estimates required sample size under classic power assumptions.
More in Statistics & Experiments
free
Statistics
Sample Size — A/B conversion lift (power 0.8, α 0.01)
Estimate required sample size for a/b conversion lift at power 0.8 and alpha 0.01.
Advanced
Openfree
Statistics
Sample Size — A/B conversion lift (power 0.8, α 0.01)
Estimate required sample size for a/b conversion lift at power 0.8 and alpha 0.01.
Advanced
Openfree
Statistics
Sample Size — A/B conversion lift (power 0.8, α 0.01)
Estimate required sample size for a/b conversion lift at power 0.8 and alpha 0.01.
Advanced
Open