At a glance
D1 Retention % is the share of a cohort that returns and performs the retention event on the day after their first activity in Amplitude. It is the earliest read on whether a first experience was good enough to bring users back, making it the most sensitive onboarding signal. The card pairs with sibling metrics in the Analytics category to build a complete diagnostic picture; cross-reference the related cards listed below for context.
| What it counts | The percentage of users in a cohort who return and perform the retention event exactly one day after their first activity, using Amplitude’s N-day retention method. |
| Sample type | Backend API data from Amplitude, refreshed on the standard data refresh. |
| Why it matters | Day-one return is the strongest early indicator of onboarding quality and first-impression fit. It moves fast in response to product, content, and acquisition changes. |
| Reading the value | Compare the current 30-day window against the prior period. A falling D1 means newer cohorts are coming back less, often before downstream retention reflects it. |
| Currency | percent |
| Time window | 30D vsP |
| Alert trigger | <30% |
| Sentiment key | amp_retention_d1 |
| Roles | owner, marketing |
Calculation
Calculated automatically from your Amplitude data. Amplitude groups users into cohorts by their first event, then measures the percentage who returned and performed the retention event on day 1, the day immediately after first activity. This card reports that day-one percentage over the 30-day window and compares it against the prior period. See the At a glance summary above for what the metric tracks and the worked example below for a typical reading.Worked example
A representative reading of D1 Retention % for a typical merchant on Amplitude. Suppose recent cohorts return at 34 percent on day 1, down from 41 percent in the prior period. The 7-point fall is an early warning that something about the first experience has weakened, perhaps a slower landing page, a new onboarding step, or lower-intent traffic from a recent campaign. Because D1 reacts quickly, catching it here gives time to fix before D7 and D30 erode. Use Vortex Mind to trace which acquisition source or release coincided with the drop; for natural-language exploration, ask Ask Viq to compare D1 across devices.Sibling cards merchants should reference together
| Card | Why merchants reach for it |
|---|---|
amp_retention_d7 | The mid-curve stickiness gauge that D1 often leads. |
amp_retention_d30 | The long-run tail that a weak D1 tends to drag down. |
amp_retention_curve | The full curve that puts the D1 point in context. |
amp_stickiness_dau_mau | A complementary view of how often active users return. |
amp_new_users | The cohort size feeding D1; a shift in mix can move the rate. |
Reconciling against Amplitude
Where to look in Amplitude’s own dashboard: Open the Retention chart, set the method to N-day, and read the day-1 column for your start and return events. Confirm the cohort range and segment filters match the Vortex IQ profile. Event Segmentation can verify the return-event volume, and the Dashboards section may pin a saved retention chart for reference. Why the Vortex IQ value may legitimately differ:| Reason | Direction | What to do |
|---|---|---|
| Period boundary. Vortex IQ uses a 30-day rolling cohort window by default; an Amplitude retention chart may use a different range. | Variable | Match the cohort date range in the Amplitude retention chart. |
| Time zone. Amplitude defines day boundaries by the project time zone; Vortex IQ aligns to the merchant reporting time zone. | Marginal | Confirm the project time zone matches your reporting time zone. |
| Filter or segment scope. Profile-level filters (platform, B2B, test users) change which cohorts feed the rate. | Variable | Apply the same segment to the Amplitude retention chart. |