No matter how much you make or what kind of work you do, at some point in your career you have probably asked yourself: “Am I getting paid what I deserve?”

Chances are, the answer is no — particularly if you have never actively negotiated your salary.

For most of us, negotiations of any kind are stressful, awkward and uncomfortable. We don’t want to look greedy and fear the conversation will strain our relationship with our boss, or possibly cost us the job altogether. But despite how awkward it may feel, learning to ask for a raise is critical. According to a study in the Journal of Organizational Behavior, not negotiating during an initial job offer could cost you more than $600,000 over the course of a typical career.

See also: 9 phrases that make you sound less experienced than you are

If you’re contemplating a salary negotiation, there are plenty of books, seminars and articles to help you develop the best tactics. The topic has also been the focus of numerous university studies, with experts looking at every detail from when to ask to what to eat beforehand.

Here are five surprising facts to help hone your negotiation strategy.

1. It’s best to ask for a raise early in the day

In a Forbes article, Seattle psychologist Shannon Kolakowski recommends asking for a well-deserved raise in the morning when your boss is likely to be “more moral” than later in the day.

This thinking is based on a study published in Psychological Science that showed the “morning morality effect.” In a series of experiments, participants were less likely to engage in unethical behavior in the morning than when they performed the same tasks in the afternoon. The bottom line? Negotiate in the morning when your boss’ “morning morality” may push him or her to give you what you deserve.

2. It’s best to ask on Thursday or Friday

Conventional wisdom says that people get more frazzled, tired and disagreeable as the work week plods on; therefore it can be better to approach a boss early in the week when they’re still fresh and in a good mood.

However, Psychology Today reports that the opposite might be true. According to a psychologist at McGill University, we’re more focused on getting things done early in the week, so Monday and Tuesday are all about setting goals, assigning responsibilities, organizing work and just being productive. People (aka, your boss) are more likely to be open to negotiation and compromise on Thursday or Friday, since they want to wrap everything up before the end of the week.

3. It helps if you're hungry

If you’re hesitant to approach your boss, you may be better off skipping breakfast that morning. A study out of Cornell University and Dartmouth College found that hunger propels motivation and increases your sense of entitlement to a reward, be it food, money or a promotion.

4. Offer a salary range to get better results

In most discussions about negotiation tactics, experts typically advise against giving a salary range because it’s too easy for your manager to jump on the low end. But a study from Columbia University and discussed in Quartz suggests that offering a range can lead to better results than just going with one number.

When you provide a proposed range, you’re explicitly setting the bottom and your boss will assume you won’t take anything below it. People don’t necessarily make that same assumption when you give a single figure. In addition, there’s the politeness factor. People are also less likely to go way below the bottom of the range, but they don’t have similar qualms about going below a single number offer.

5. Just ask… because it’s likely to work

The encouraging news for anyone who has been reluctant to ask for a raise is that the odds are in your favor. A study by Payscale found that three-quarters of people who asked for a raise saw their paychecks go up: 44% received the amount they asked for; 31% got less than what they asked for, but still received a bump in salary. Those are fantastic odds to have on your side.

The bottom line: In an ideal world, an employer would proactively recognize and financially compensate solid performance, talent and hard work. But that’s not the way it works in most companies. Few people are offered sizable raises unless they ask for it. Yes, it can be stressful, but a few short minutes of discomfort can have a major impact on your entire career.