At a glance
Cohort Retention D30 % is the share of a signup or first-action cohort that comes back and performs a qualifying event 30 days later. It is the medium-horizon counterpart to your day-7 number, and it tells you whether new users settled into a habit or quietly churned after the novelty wore off. In Mixpanel terms, this is a retention report grouped by acquisition cohort, read at the day-30 column. Healthy D30 is the strongest leading indicator of repeat purchase and lifetime value, because users who are still active a month in tend to stay. A weak D30 after a healthy D7 usually means onboarding wins attention but the product or store fails to build a lasting reason to return.
| What it counts | The percentage of users in a defined cohort (typically grouped by their first event or signup date) who fired a qualifying return event on day 30 after joining. |
| Sample type | Backend API data from Mixpanel retention reports, computed per cohort against the project’s event stream. |
| Why it matters | D30 retention separates a one-time spike in signups from real, compounding growth. It is the clearest early proxy for repeat purchase and customer lifetime value. |
| Reading the value | A higher percentage is better. Read it alongside the D7 figure: a strong D7 that collapses by D30 points to a habit problem, not an onboarding problem. |
| Currency | percent |
| Time window | 90D vsP |
| Alert trigger | <15% |
| Sentiment key | mix_cohort_retention_d30 |
| Roles | owner, marketing |
Calculation
Vortex IQ reads your Mixpanel retention report grouped by acquisition cohort and takes the day-30 retention column. For each cohort, the numerator is the number of users who fired the qualifying return event on day 30 after their first event, and the denominator is the original cohort size. The card surfaces the blended D30 percentage across recent cohorts over the selected window, compared against the prior equivalent period. Because true D30 requires a cohort to have aged a full 30 days, the most recent fully measurable cohorts are the ones the card relies on, and very young cohorts are excluded until they mature.Worked example
A representative reading of Cohort Retention D30 % for a typical merchant on Mixpanel. Suppose 1,000 shoppers placed their first order or signed up during the week of 14 May 26. Thirty days later, on around 13 Jun 26, you check how many came back and fired a qualifying event such as a repeat session or a second purchase. If 185 of them returned, your D30 retention reads 18.5%. The prior cohort sat at 22%, so the card shows a softening trend but stays above the 15% alert floor. You note that D7 for the same cohort was a healthy 41%, which tells you the drop-off happened after the first week, so you focus on week-two and week-three re-engagement (email flows, restock prompts) rather than onboarding. For deeper investigation, use Vortex Mind to trace upstream causes; for natural-language exploration, ask Ask Viq.Sibling cards merchants should reference together
| Card | Why merchants reach for it |
|---|---|
mix_cohort_retention_d7 | The earlier checkpoint. Compare D7 to D30 to see whether churn happens in week one or later. |
mix_retention_curve | Shows the full decay curve, so you can see exactly where retention flattens or falls off. |
mix_worst_decaying_cohort | Pinpoints which acquisition cohort is bleeding users fastest, often tied to a campaign or channel. |
mix_stickiness | DAU/MAU stickiness is the habit signal behind durable D30 retention. |
mix_new_users | New vs returning users frames how much of your base is repeat versus first-time. |
Reconciling against Mixpanel
Where to look in Mixpanel’s own dashboard: Open your saved Retention report, set the birth event to the same first action the card uses, set the return event to the same qualifying event, and read the day-30 column for the cohorts in your window. The blended figure on the card should track the average of those cohort rows. Make sure the report is set to the same retention type (recurring vs unbounded) that the card expects, because the two compute the day-30 column differently. Why the Vortex IQ value may legitimately differ:| Reason | Direction | What to do |
|---|---|---|
| Cohort maturity. Very recent cohorts have not aged a full 30 days. | Vortex IQ excludes immature cohorts, so its blend may read higher or lower than a report that includes them | Compare only fully aged cohorts in both views. |
| Retention type. Recurring vs unbounded retention count the day-30 return differently. | Variable | Match the retention type used by the card. |
| Event definition. The birth or return event differs between the report and the card. | Variable | Align both event definitions before comparing. |