Compatibility apps return a percentage — 87% of affinity, for example — and this apparent accuracy is what makes them convincing. It's worth understanding where this number comes from, what it really represents, and what is known about what makes a relationship work.
The short answer: the percentage measures the similarity between responses that two people gave to a questionnaire. This is real but limited information—quite different from a relationship diagnosis.
Where does the percentage come from?
In apps that do this with any seriousness, the mechanism is transparent and reasonable:
- Each person answers questions about values, habits, plans, and preferences.
- For each question, she also indicates how important that topic is to her.
- The system compares the responses of the two people, weighting them according to the importance each assigned.
- The result is converted into a percentage.
In other words: the percentage measures declared agreement in a questionnaire. It's legitimate information—knowing that two people disagree about having children or about religion is useful information, and it prevents discovering this too late.
In playful apps, such as those that calculate compatibility based on two names or birth dates, the calculation is different: a calculation based on letters or numbers, designed to always return the same result for the same input. It's entertainment, and some say so.
What this percentage fails to capture
Here's the limit, and it's a big one.
Como duas pessoas lidam com o conflito
The most crucial point, and precisely the one that no questionnaire can capture, is this: every couple disagrees; the difference lies in how the disagreement is handled—whether there is listening, whether there is contempt, whether there is reconciliation after the argument. This only emerges through living together.
A química presencial
Two people with nearly identical responses may feel no attraction when they meet. And the opposite happens all the time.
O que as pessoas respondem versus o que fazem
Questionnaires capture what someone it says To value something. It's not always what a person practices—not out of bad faith, but because self-knowledge is limited and there's a natural tendency to respond with what sounds best.
Mudança ao longo do tempo
People change their priorities, their cities, their phases of life. A compatibility measured today describes today.
Circunstância
Life stage, distance, financial situation, and support network all weigh heavily—and are not factored into the equation.
What is known about predicting relationships?
Researchers studying the formation and maintenance of couples have reached a consistent, albeit somewhat uncomfortable, conclusion for the industry: individual characteristics and declared similarity between two people explain little of the couple's future satisfaction.
What predicts it best is the dynamics between the two people — how they talk, how they treat each other when they disagree, how much support they offer — and this dynamic only exists after they get to know each other. There's no way to measure it beforehand.
None of this makes the apps useless. It just shifts their merit: the value lies in... increase the number of possible encounters, It's not about predicting which one will work.
How to use the questionnaire the right way.
Percentages are poor as verdicts but good as topics for conversation. Some concrete questions are worth more than any index:
- Do you want to have children? In what timeframe?
- How do you envision the next five years, in terms of city life and work?
- How do you handle money — together, separately, how do you decide?
- What role does each person's family play in their daily life?
- Do religion and religious practice matter?
- How does each person usually react when they are upset?
Disagreements on these points are the most damaging, and it's best to discover them early. Note that the last question is the one that automated questionnaires least accurately address, yet it's the most important.
What to do with a low — or high — result.
A low score isn't a definitive answer. It might simply mean you responded differently to important topics, which is worth discussing. A high score also doesn't guarantee anything: agreeing on paper is easy.
The real test is living together for a few weeks, paying attention to things that no app measures — whether the person keeps their promises, how they treat the person serving at the table, how they react when you disagree with them.
Where apps actually help.
Expanding your reach. Outside the app, you know who's at your work, in your neighborhood, and in your circle of friends. Proximity determines who enters your life, and that's quite limited.
Here are some precautions that are always worthwhile: maintain an honest profile, have a conversation before meeting, have the first meeting in a public place, have someone know your location, and be immediately suspicious of anyone who avoids video calls or asks for money — the most common pattern in relationship scams.
SEE MORE:
- Why can't any app predict a face?
- Facial recognition: what the technology does
- Safe apps for chatting with people nearby.
Privacy of responses: who else reads what you answered?
Compatibility tests ask questions that no one would answer a stranger on the street: sexual habits, religion, income, alcohol use, desire to have children, relationship history. From a data protection standpoint, much of this is sensitive information, with enhanced protection under the General Data Protection Law precisely because it allows for discrimination.
Before responding, look for three objective answers in the privacy policy: whether the responses are used for ad targeting, whether they are shared with partner companies, and how long they are stored after you stop using the service. A reputable service answers all three in simple language.
It's also worth using the option to delete the account, and not just delete the app. App stores now require this step within the app, and it's what triggers the removal of the profile on the server. After that, check if your email has stopped receiving communications; if they continue, there is a formal request for deletion provided for by law.
What to check on a dating app before installing
- Blocking and reporting tools Visible in the profile and in the conversation, not hidden in menus.
- Profile verification Using a selfie or document, this reduces the number of fake accounts, but it's not a guarantee.
- Location controlApproximate distance is acceptable; displaying exact location in real time is not.
- Permissions requestedContacts and SMS messages have no relation whatsoever to the service.
- Billing model Explained before registration, with no essential feature hidden behind a card test.
- Data policy that will determine the fate of the photos and questionnaire responses.
- Option to pause the profile Without deleting the account, useful for those who want to disappear for a while.
A good sign is often subtle: apps that take security seriously maintain a help center with guidance on scams and harassment, and explain what they do when they receive a report. Where this material doesn't exist, moderation probably doesn't exist either.
Safety when transitioning from the app to real life.
No compatibility percentage can replace basic care on a first date, and that's where technology really helps. Before even making a date, a short video call can eliminate a good portion of fake profiles, because those who use someone else's photo avoid appearing in person.
- Find it in a public place. It's busy, and you can go back and forth on your own.
- Tell someone Who are you going to meet, where, and at what time?.
- Share your live location. Message a trusted person via messaging app for a limited time.
- Do not send money., Not even for a touching emergency: asking for money before the first date is the classic script for a romance scam.
- Do not share intimate images. Blackmailing people you don't know personally is a crime and happens frequently.
- Be wary of rushing to exit the app. and switch to another channel right after the first few messages.
If something goes wrong, save screenshots of the conversations before blocking, because the history usually disappears when you end the contact. Threats, extortion, and the dissemination of intimate images without consent are crimes under Brazilian law and can be reported to the police, including specialized cybercrime units.
Common mistakes people make when using compatibility tests.
The most costly mistake is using percentages to end or push a relationship to its limits. A low number becomes a self-fulfilling prophecy because the person starts interpreting any friction as confirmation. A high number has the opposite and equally bad effect: it makes people overlook signs that deserved to be discussed.
Another mistake is answering the questionnaire thinking about the ideal answer instead of the true one. The result then describes a person who doesn't exist, and the real encounter dismantles that construction in a few minutes. Since the instrument is self-reported, its value is only as high as the honesty of the answers.
There are even those who repeat the test several times until they arrive at a satisfactory result. This clearly shows what the number is: a result sensitive to small changes in response, not a stable measure of a couple.
Frequently asked questions about app compatibility
O algoritmo melhora com o tempo de uso?
It improves by showing profiles similar to those you usually like, which is a recommendation based on behavior. This helps filter, but tends to narrow down the options and has no bearing on predicting the duration of a relationship.
Mapa astral e signo entram nesses cálculos?
In some apps, yes, it's a declared filter. It's a personal preference, similar to filtering by height or musical taste. Just don't confuse it with prediction: if it's important to you, it's a legitimate selection criterion, not a compatibility measure.
Vale pagar pela versão premium?
What the paid version usually delivers is volume and convenience, such as more likes per day or seeing who liked your posts. There is no paid version that improves forecasting, because forecasting is not what is being sold.
O que funciona melhor que a porcentagem?
A conversation about concrete issues before the meeting: what each person expects, routine, money, children, distance. Five minutes talking about these topics reveals more than any index calculated from a form.
