Use it for

  • Support a structured review of a properly designed conversion experiment.

Before you open it

Public resource; no sign-in needed to read.

  • Predefined hypothesis, test design and reliable visitor/conversion counts.
  • Browser; aggregate counts for variants A and B.
GIVE CREDIT WHERE IT BELONGS

The people behind the resource

Resource notes and library artwork curated by Paid Media Collective. The original work belongs to the contributors credited above. Inclusion does not imply a partnership or a member submission.

Public web calculator; no licence to redistribute its code established.

Source review and practical limitations

Source reviewed · 6 September 2026. We reviewed the source to the level stated here; tools, courses and account workflows have not been tested end to end.

  • Calculator arithmetic was not independently validated.
  • Significance alone does not establish causality; avoid treating repeated checks as a valid stopping method.