Metrics & stats
Understand which variant wins at a glance — without needing a data team.
The numbers explained
- Impressions
- How many times users were shown a particular variant. Recorded each time your code calls ff.impression().
- Conversions
- How many of those users went on to complete the goal event. Recorded when your code calls ff.track().
- Conversion rate
- Conversions ÷ Impressions × 100. The variant with the highest rate is highlighted in the results table.
Reading the results table
In the experiment detail view, each row is a variant. Columns show impressions, conversions, and conversion rate. The highest-converting variant is highlighted so you can see the winner at a glance.
Vexil shows raw rates. For high-stakes decisions, run the numbers through a significance calculator (like a chi-square test) to confirm your results aren't due to random chance before declaring a winner.
Stopping an experiment
Click Stop on the experiment card when you've collected enough data. The results freeze at that point. Once stopped, you can update the flag to permanently serve the winning variant to all users.