Build a week-one retention table from a signup cohort

Product asks what fraction of signups from a given week are still active a week later, and the next week after that.

AdvancedRead 7 minDoing: an hour to 90 minutes10 steps

What you'll have at the end

A table with one row per signup week and one column for each week after, each cell either a retention percentage or left blank for a week that has not happened yet for that cohort.

Before you start

You need

A signups table with one row per user and a signup date, plus an activity or events log you can join to it by user id.

Not covered

Retention broken out by acquisition channel, plan tier, or any other segment; this builds the single overall cohort table only.

Leans on

10 steps

Where to go next

Flag lapsed customers who've gone quiet

go there to name the specific customers who have gone quiet right now, rather than the aggregate share of a whole signup week that came back

Checked 26 Aug 2026

Part of the SQL for Data Analysis cookbook