stickiness

Also called: DAU/MAU, DAU/MAU ratio, WAU/MAU, stickiness ratio, stickiness metric

DAU divided by MAU (or WAU by MAU): the share of monthly users who show up on a typical day or week. Only meaningful at the product’s natural usage rhythm.

Stickiness measures how often the people who use a product in a month come back within it. The classic version divides the average daily audience by the monthly one:

$\text{Stickiness}_{\text{daily}} = \frac{\overline{\text{DAU}}}{\text{MAU}}, \qquad \text{Stickiness}_{\text{weekly}} = \frac{\overline{\text{WAU}}}{\text{MAU}}$

where the bar means the average over the days (or weeks) of the same month. A DAU/MAU of 20% says the typical monthly user is active on about 20% of days, roughly 6 days a month. It ranges from 1/30 (everyone comes exactly once) to 100% (everyone comes every day).

Unlike MAU, stickiness is a ratio of habit, so it doesn't rise just because marketing brought more people. That makes it useful for comparing segments, platforms or product versions of different size, and for spotting a feature that turns occasional users into regular ones.

It only makes sense at the product's natural rhythm. A chat app should be judged by DAU/MAU; a product people need weekly (splitting shared bills, grocery planning) by WAU/MAU; a travel booking app by neither, because users with one trip a year are perfectly healthy. Mixed audiences need care as well: when the share of low-frequency segments grows, overall stickiness falls even if nobody's behavior changed (a mix shift), so read it by segment.

Example

Halves in June: average DAU 6,000, average WAU 18,000, MAU 40,000.

DAU/MAU = 6,000 / 40,000 = 15%
WAU/MAU = 18,000 / 40,000 = 45%

Halves is a weekly product (people add expenses when they pay for something shared), so the team headlines WAU/MAU. By each user's main group type:

Segment	MAU	Average WAU	WAU/MAU
Flats	14,000	9,800	70%
Couples	10,000	3,400	34%
Trips	16,000	4,800	30%
Total	40,000	18,000	45%

In July the summer travel season doubles the trip segment to 32,000 MAU with an unchanged 30% (9,600 WAU); flats and couples stay the same. Total WAU = 9,800 + 3,400 + 9,600 = 22,800; total MAU = 14,000 + 10,000 + 32,000 = 56,000; WAU/MAU = 22,800 / 56,000 ≈ 40.7%.

Overall stickiness fell by more than 4 percentage points while every segment's habit stayed exactly the same. The drop is a change in who uses Halves, not in how they use it.

Common mistakes

Using DAU/MAU for a weekly or monthly product. It will look "low" forever; pick the ratio that matches the natural rhythm.
Mixing windows. Average DAU over June divided by MAU for a rolling 30 days ending 15 July compares different people.
Reading a drop as lost engagement. A wave of new or seasonal users lowers the ratio with no change in habits; check segments first.
Chasing someone else's benchmark. Ratios quoted for social apps don't transfer to utilities, finance or travel.
Inflated activity. Server-created or passive events push DAU up faster than MAU and make stickiness look better than it is.

Learn it in the course

DAU, WAU, MAU and stickiness · Count active users at the rhythm people actually use the product.