Metric
Power-user curve (L28, or L7 for workweek products)
Histogram of monthly active users by how many days (1-28) they did the core value event. A right-leaning smile shows a daily core; successive monthly curves should shift right. Use L7 (days out of 7) for workweek products.
Plain label: users by days active in the monthAlso known as: L28, L30, L7, power user curve, active-days histogram
It shows the power-user core that averages hide, and it can be built for any important action, not just opens. Healthy B2B L7 curves often smile through about five days; investing, travel and professional networks can be left-leaning and still be good businesses. There is no universal good number: compare trends and category peers.
Sources
The Power User Curve · a16z (Li Jin and Andrew Chen), 2018
Benchmark confidence A. A primary source for the benchmark.
Book content is paraphrased, never quoted at length. Last verified October 24, 2026.
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