How Many Calories Should You Eat?

The Internet is full of calorie calculators. They all ask you the same questions, and then confidently tell you exactly how much to eat. They're all wrong. People are more complicated than a simple formula. Luckily, finding out how many calories you need is not complicated. It just takes a little time.

Let's start with a calculator of our own. After you fill out your numbers, you'll see that this one has a twist.

Please fill out the calculator, otherwise the rest of this article won't make much sense.

As you can see, the calculator only gives you a rough number. Where in those ranges do you fit? Could be anywhere. Some calculators try to take more factors into account. They don't improve the accuracy that much. So there is quite a bit of uncertainty in these numbers.

You should also consider what you actually eat. If your goal is 2000 calories and you're a bit sloppy, you could easily end up eating 2500 calories instead. Even if you're super careful, you might still get tripped up. Perhaps your scale is 5% off. Or you eat a cookie that a coworker brought to the office.

Worse, you could be relying on the packaging to tell you how much it contains. How much chicken is there in a 12.5 oz can of Swanson Canned Chicken Breast? The four cans I weighed were all 8.0 oz or less. The FDA says that a product may contain 20% more calories than it says on the label. Simply counting calories has a lot of uncertainty baked in!

The good news is that we're creatures of habit. Our days are mostly the same, and so are our food habits. If you're off by 12% one week, you are probably off by 12% every week. Once you find a calorie number that works for you, it will probably keep working for you. (Until your habits or weight change significantly.)

Finding the number is also easier than you might think, it just takes some time. The secret is simply trial and error.

1. Pick a daily calorie goal. You can start by picking a number from the range calculated above. You probably already know whether you are someone who gains or loses weight easily. Pick on the low or high end of the range accordingly. If you're tracking calories already, pick a number based on that.
2. Every day, do your best to eat that many calories.
3. Weigh yourself every day. Track your weight using some app that calculates a moving average. You care about the trend, not the day-to-day variations. Google Fit does this. WeightGrapher is another free option.
4. Once a week, look at your weight trend. If it's not doing what you want, adjust your daily calorie goal up or down by 100 or 200 calories. (Try to gain/lose no more than 1lb per week.)

How you eat those calories is up to you. A simple way is to eat a quarter at breakfast, a quarter for lunch, a quarter for dinner, and a quarter for snacks. To help you keep track, use a calorie tracker like Cronometer and a meal planning tool like Meal Inventor.