Three middle-aged men in suits are drinking wine at the bar at Le Diplomate, and Michal Matejczuk suspects one of them carries one of those heavy metallic credit cards. “Whenever you get a heavy card, you always know that this person spends a lot,” he says.

Their tucked-in shirts are also a good indicator. “If you’re tucking your shirt in, you mean business right now,” he says. Also, “If you’re wearing long sleeves right now in the dead heat of summer, you’re going out and you’re spending a lot of money.”

Over the years, Matejczuk has worked as hotel “guest service agent,” cashier, and server. Currently, he is general manager and executive chef at Dacha Beer Garden, and before that, he was an assistant general manager at Barcelona Wine Bar. I’ve brought him to Le Diplomate to explain exactly how restaurant staff think about diners when they walk in the door. We’re sitting at the bar, scoping out diners.

A pair of men who Matejczuk quickly identifies as gay—one with a beer, the other sipping a martini—are having dinner with a female friend, who’s not drinking. In the middle of a table, a cheese plate, which Matejczuk sees as a sign that they’ll be here awhile. “Gay men have a higher check average… I’m thinking maybe $125, $150?”

Matejczuk proceeds to go around the room and guess other tables’ check averages. The foursome who look to be in their 60s on a double date? Matejczuk expects they’ll spend around $300. “When it’s this smaller older group, they tend to pay a lot more.”

The dad in a pink button-up having dinner and sharing a bottle of wine with his wife and their adult daughter? $150 to $200. “Dad’s probably got a steak. Mom’s probably got a well-composed salad or a chicken dish or fish. I can’t read the daughter, though.”

Near the window, three women who look to be in their early 20s are sitting without drinks. “I wouldn’t expect too much. I feel like they’re lounging because it’s nice outside. They’re probably on a budget.”

Meanwhile, a big group of teens and adults are huddling by the entrance. “That’s probably going to be a two to three hour table right there, so that really hurts your chances of tips,” he says. Plus, only the adults—and probably not even they—will be drinking, meaning a server could be missing out on $20 to $30 per person. “People with kids? Hmm, no thanks.”

Whether Matejczuk’s evaluation of the dining room is accurate or not, this isn’t just the way he thinks; it’s how a lot of servers think. The fact of the matter is, as soon as you enter a restaurant, the staff is probably sizing you up. Are you someone who’s going to order a lot of food and expensive drinks, then leave a big tip? Will your table be a total nightmare with no payoff? For many servers, their livelihoods depend on making snap judgements and sometimes relying on stereotypes.

“Everyone gets sized up, pretty much. We’re always just looking for money. It’s never really about anything but money and hassle,” says Brian (not his real name), a server of seven years who previously worked at P.J. Clarke’s. (Several of the people in this story requested anonymity so they could speak candidly without jeopardizing their jobs.)

Often, you’re sized up before you even walk in the door. “We Google everyone,” says Amy (not her real name), who works at two buzzed-about D.C. restaurants that she didn’t want to name on the record. “I would say pretty confidently that most places that take reservations have looked you up already… We just look for what you do. If there’s a photo, that’s helpful. We don’t save the photo—that’s creepy. I’m sure some places might.”

Your server would never dare bring up something from your LinkedIn or Facebook page, but your background may subtly inform their interactions with you. Amy claims it won’t change the quality of service at the restaurants where she works, but “the more information, the better. Knowing more always helps.”

When you walk in the door, the first thing servers will notice is what you’re wearing, Brian says. “If they’re dressed well, we assume they can at least afford to tip us the 20 percent we’re hoping for. If you’re not dressed well, we at least pray that you decided to save up for a good meal.”

While Armani or Hermès might seem like obvious giveaways, many servers I spoke to said clothing is often deceiving.

“The way people are in D.C., they’re always dressing to impress. They’re always looking to be the next president,” says Simon Stilwell, who previously worked at Oval Room, Rasika, and other Knightsbridge Restaurant Group establishments. Stilwell, who now works in Philadelphia, has held a variety of roles in his 15-year restaurant career, including general manager, beverage director, and server. He’s found that an expensive watch or well-tailored suit symbolize something more in cities like Philadelphia, because people aren’t always dressing up. In D.C., though, nice clothes don’t necessarily mean you have any money. They mean you know how to dress for your job.

“The suits can be really good if it’s lawyers and they just won their case. Suits can also be really good if they’re lawyers and they just lost their case,” says Stilwell. “You need to recommend wine to the ones who won, and Scotch and bourbon to the ones who just lost.”

All in all, though, people who actually have money are not flashy, says Zia (not her real name), a server at a popular Capitol Hill restaurant who previously worked at Georgia Brown’s, Busboys and Poets, and Paolo’s. “It’s the subtle things in life. Sure, you have on some cargo shorts and a polo, nothing name brand, but I’m going to notice the quality.”

Zia relies more often on body language or mood to read who’s going to be a big spender or tipper. That couple that’s bickering or not talking? Not promising. “The people that walk in the door and they’re happy about life and they’re ready to have a good time, that’s the easiest signifier [that] they’re about to drop some serious cash.”

Stilwell likewise finds how people carry themselves to be the most telling. Diners with money tend to have more specific tastes. For example, they might say something like, “We generally like to drink white Burgundies. What do you have?” or “I really like Brunellos.” But if someone says they want Cabernet or “Italian wine,” that’s generally not an omen for a fat check.

Many servers also have their own personal stereotypes: “Southern Dad always drinks heavy and spends money,” says Zia, who’s worked in restaurants for 11 years. “Southern Dad is always a winner.”

But Zia says her favorite tables are groups of women in their 40s to early 70s. “You’re about to make all the money,” she says. “They’re a little bit like ‘I’m going to live my life how I want.’ It’s like redoing your 20s, but now you have more knowledge of self. And you have less debt, so you can wear a pair of Ferragamo shoes, not wish for them.” The groups of older women, she says, are the ones she counts on to immediately order a round of Madras cocktails or cosmopolitans. “A woman that starts with a martini and lets you know early in the game that she wants wine, you’re about to have the best night.”

At the same time, Amy says groups of millennial women are often perceived the opposite way. “I’ve heard this many times: Young white women, if they look like they’re in their early to mid-20s, you’re like, ‘OK, they’re not going to spend any money,’” she says. Plus, servers often expect they’re going to linger at the table a little too long.

Beyond that, perceptions about age are mixed. Some servers say older generations still have it in their minds that 15 percent—not 20 percent—is standard gratuity. But that’s not consistently the case, and even if septuagenarians tip less percentage-wise than 20-somethings, they might spend more, making the overall tip above average.

Whether or not the staff pools tips can make a difference in how servers approach a table. In a pooled house, servers are more likely to help each other with a “whale”—the term used for a big spender. They also may be less likely to immediately stereotype people based on who they think has money. In a restaurant where it’s every server for him or herself, there’s more likely to be “sharks,” who will try to poach the perceived best tables.

“I’ve been a shark before,” Zia says. “If there’s someone who’s a weaker server than you and maybe can’t handle all their tables, or someone’s asking them some serious wine questions, and they’re fumbling with it, I’ll take the table… I always ask, but I don’t ask in a way that you can say no to me.”

Depending on the restaurant, staff can get very competitive for potential big spenders, especially when it’s been a slow week or you have a lot of sharks, Zia says. “I’ve stolen people’s tables before. You didn’t get here fast enough, so here I am.”

Stilwell says many high-rolling regulars request specific servers. That often ticks off less veteran staff, but Stilwell would encourage them to cultivate their own relationships by remembering names and drink orders and making notes in the OpenTable system. “Once the trust was built between you and them, I found it very easy to, on certain days, escalate their check exponentially,” he says. The guy that usually went for a $150 bottle of wine might be talked into a $500 bottle on occasion if he has a rapport with the person selling it.

Other times, servers might try to suck up to whoever holds the reservation book. At Barcelona, servers were always begging Matejczuk for certain tables that they perceived to have a lot of money. The restaurant had identifiers in its system noting “birthday,” “bachelorette party,” “anniversary,” or “VIP.” “VIPs, they’re just screaming,” he says. “It’s just this small little note that they think, ‘I’m going to get the most money right now.’”

On the flip side, there’s a pervasive stereotype that tourists and foreigners don’t tip well. After all, the tipping system is different or non-existent in other countries. “They’re not going to tip me. Why are are you giving them to me?” servers would sometimes complain to Matejczuk if they had to wait on foreigners, especially if it was one of the last tables of the night. (Matejczuk is himself an immigrant from Poland.)

But does the perception that someone’s going to spend a lot of money actually change how they are treated? Often the answer is yes, say several industry veterans. That’s not to say that everyone else won’t get good or even great service. But a potential whale undoubtedly will receive the royal treatment. The server will also likely try to sell up and talk more about the pricier bottle of wine or tasting menu.

“I’m definitely going to mention specials to people I think are willing to spend the money on specials. And I definitely am going to mention the higher priced cocktails and liquors,” says Brian.

At the end of the day, profiling only goes so far. Servers can Google you, check out your clothes, and judge your drink order all they want, but people are unpredictable, and there are never any guarantees.

“You literally don’t know what’s going to happen. There’s always this element of surprise,” says Amy. “Human beings are fascinating things.”

Illustrations by Lauren Heneghan