In order to reduce food waste, FSIS recommends that regardless of the date, consumers should evaluate the quality of the food before deciding to eat it or throw it away. (The one exception: Federal law requires a date on all infant formulas for safety and it should always be followed.) So what exactly do expiration dates mean then, and how long is food really good for? With help from experts and product manufacturers, Real Simple compiled this simple guide to reading expiration dates and when to worry about food safety, so you can shop smarter and waste less.

How to Read Expiration Dates

Depending on where you live, you may see different dates on your food and each has a different purpose. Here’s a bit of clarity based on information from the Institute of Food Technologists (IFT) and FSIS. Best If Used By/Before: This is a quality assurance date and serves as a “suggestion” for when the taste and quality of food are at their peak. It is not a purchase or safety date. Use By: This is the suggested date by when you should eat the food. But just because it’s a day or two past the use-by date doesn’t mean that consuming it will make you sick, although you should evaluate the quality of the food yourself after this time. It is not a safety date, except when used on infant formula. Sell By: This is not a safety date, but rather a date for retailers that helps them determine how long an item should remain on the shelf. According to the IFT, “one-third of a food’s shelf-life remains after the sell-by date for the consumer to use at home.” Freeze By: According to the USDA, this date indicates when a product should be frozen to maintain peak quality. It is not a purchase or safety date.

How Long Are Foods Good After the Expiration Date?

“With an exception of infant formula, if the date [on your food] passes during home storage, a product should still be safe and wholesome if handled properly until the time spoilage is evident,” according to FSIS. You can tell if a food is spoiled if it has an off odor, flavor, or texture. With that in mind, here are the recommended expiration date guidelines for common foods thrown away too early.

Food Expiration Date Chart

How Long Does Frozen Food Last?

Items from the freezer section are safe to eat indefinitely. They have expiration dates because they won’t taste good forever; flavor and texture break down over time. Once you open a bag of frozen peas or corn, pour out a portion rather than reaching in with your hand, which can introduce bacteria. (Bacteria can’t grow in the freezer, but they can survive. If you don’t cook an item after you defrost it, the bacteria could still be dangerous.)

How Long Do Leftovers Last?

Have a giant pot of chili that would feed a team of football players? Invite them over. According to the USDA, most refrigerated leftovers last 4 days, tops. Dishes that contain seafood or uncooked ingredients, like mayonnaise, spoil faster; so be sure to eat them within a couple of days. Don’t let uneaten food linger on the counter for more than 2 hours. The longer a dish sits at room temperature, the more susceptible it is to bacteria growth. It’s fine to put warm food in the refrigerator or freezer. When handling a dish that will take many hours to cool fully—a huge stockpot full of stew, say—transfer it to several smaller containers first. Meanwhile, leftover meals you freeze yourself should be tossed in 3 to 4 months. After that, they can become icy and start to take on the flavors of other foods in the freezer. Are you still concerned your food has gone bad? Consult our handy food storage guide, and find out how long everything lasts in the fridge, freezer, and pantry. You can even print out the version below and put it up on the fridge for future reference.