# A/B test experiment reports

> Report on A/B tests you run with your own tool: send the variant as a property, then compare conversion rates per variant with statistical significance.

Privatus Analytics doesn't run experiments. It reports on the ones you run with your
own code or tool (GrowthBook, Statsig, VWO, Optimizely…).

## Send the variant

Add the experiment and variant as properties on every hit:

```js
privatus.props({ experiment: 'checkout_2026_09', variant: 'b' })
```

Set them before the first pageview (use
[manual mode](/docs/tracker/manual-mode) if the variant is assigned after
load), or send them on the events that matter.

## The report

**Experiments** takes a property that holds the variant and a goal, and
shows per variant:

- visits and conversions,
- the conversion rate, with the difference from the control,
- the **statistical significance** of the difference.

Wait for significance before deciding, and decide the sample size up
front: stopping as soon as a result looks significant inflates false
positives.

Visits never outlive the UTC day, so an experiment that spans several
visits by the same person counts each visit separately.