For the past six months, has been selling investors on a user growth metric it didn't used to care much about: Daily active users. That's the same metric and use, and one that has become more popular among social companies than the more traditional "monthly active user" number.
On the DAU, front, Twitter's user growth looks good, which is a key reason it's focusing on that figure. When Twitter reported earnings Thursday, the company said its daily user base grew 12 percent in Q2 over the same period last year, marking the third straight quarter that DAU growth was in the double digits. (Twitter's MAU growth, for comparison, was just 5 percent year over year, and the company didn't add any new users in Q2.)
There's just one problem with this DAU focus: Twitter doesn't actually share how many daily users it has. Which makes 12 percent growth hard to appreciate. That's 12 percent growth from what?
Well, let's do a little math.
When Twitter reported its Q2 earnings in 2015, the company tweeted that its DAU-to-MAU ratio was 44 percent in its top 20 markets. Let's assume that ratio is also true for Twitter's total user base at the time, which was 304 million users. That would mean Twitter had about 134 million daily users in Q2 of 2015.
Twitter then reported a 5 percent year-over-year increase in DAUs the following year. That means in Q2 2016, Twitter had about 140 million DAUs.
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Fast-forward to present day, when Twitter reported a 12 percent year-over-year jump in DAUs for Q2 2017. That would make Twitter's current DAU count: 157 million users.
That aligns perfectly with some details Twitter COO Anthony Noto shared on Thursday's call. When asked about the ratio, Noto pointed back to a 48 percent DAU-to-MAU ratio Twitter shared at an Analyst Day presentation in 2014.
"Our DAU-MAU ratio, regardless of how you measure it, hasn't changed meaningfully or substantially over the last couple of years," Noto added.
Assuming that is still the case — it hasn't changed meaningfully or substantially — that would put Twitter's daily user count at 48 percent of its current MAU count of 328 million, which would tally to 157 million users. Snapchat, for comparison, claims 166 million daily users.
This is an estimate, of course, but it seems to work. Without something more concrete from the company, an estimate will have to do. We've shared our math with Twitter, and a spokesperson replied: "We disclose DAU growth trends, which in Q2 was 12 percent year-over-year, our third consecutive quarter of double digit growth."
Why does any of this matter? Twitter claims it has a lot of room to grow that DAU number, which is true, and could mean that its business continues to grow even if its MAU total stays flat. Twitter says its daily user growth in Q3 is already on pace for another double digit jump.
Eventually, of course, the two numbers will get closer and closer and Twitter will need to figure out MAU growth again. Investors are already anxious about MAU flatlining — after its earnings report Thursday in which it didn't add any new MAU users in Q2, the stock was down more than 11 percent.
But if DAU growth continues to be positive and investors buy it as a legitimate sign that Twitter's existing user base is more engaged than in years past, it could buy the company some time. That's the hope, at least.
—By Kurt Wagner, Recode.net.
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