How to Find Love Online

Online dating is a circus of self-deception. There are the things that people don’t want to matter, but do–of which race is a salient example. Then there are the things that people want to matter, but don’t.

Profile text is one of these. What you write about yourself hardly makes a difference in the number of messages you get on OkCupid: we estimate that your words have about one-twelfth the impact of your picture. Many newer apps have gotten rid of personal essays altogether.

Religion is similarly irrelevant. However central religious belief may be to our 15 million users’ personal lives, in online dating it is marginal. Religious-match questions on OkCupid are often assigned the highest importance. But when you look at the data, religion is one of singledom’s self-imposed divides.

A few years ago, OkCupid brought in a statistician from Columbia to answer the question “Of all the data we collect, what matters most in creating relationships?” After months of work, he arrived at his answer, the single most important attribute: how often someone smokes. It’s one of the very few true deal breakers, although 28% of the user base says yes to “Have you smoked a cigarette in the last six months?” Followed by political intensity. Then a variety of practical concerns, like desire for children. Then, down the list, religion.

Of course, OkCupid is a mainstream site, and niche sites like JDate and ChristianMingle will no doubt find that religion is a core value among their users. But for the rest of the country, other things are more important than where you spend your Sunday mornings.

Rudder is a founder of OkCupid and the author of Dataclysm

This appears in the June 15, 2015 issue of TIME.

Contact us at letters@time.com.