Definition
The percentage of new users who return to the product exactly one day after signing up.
Formula
Users active on Day 1 / Total new signups x 100
How to measure
Track a signup cohort and measure the percentage who trigger any active-use event exactly one day after their signup date.
Why track it
D1 retention is the fastest-available retention signal, letting a team catch onboarding problems within 24 hours instead of waiting weeks for cohort curves.
Example
A mobile app's D1 retention rises from 25% to 40% after fixing a confusing first-run tutorial.
FAQ
- What is Day 1 Retention?
- The percentage of new users who return to the product exactly one day after signing up.
- How do you calculate Day 1 Retention?
- Users active on Day 1 / Total new signups x 100
- Why track Day 1 Retention?
- D1 retention is the fastest-available retention signal, letting a team catch onboarding problems within 24 hours instead of waiting weeks for cohort curves.