How to Keep Chips Fresh After Opening the Bag: 7 Easy Ways

You open a bag of chips, eat a handful and put the rest away. Two days later, they bend instead of snap. It happens to everyone, and it is easy to prevent once you know what is going on inside the bag.

Below are seven ways to keep chips fresh after opening the bag, from a no-clip folding trick to resealing the bag with heat the way the factory did. First, why chips go stale so fast.

Why do chips go stale so fast?

Two different things happen to an open bag, and they need different fixes:

• Moisture makes chips soft. Once the bag is open, chips start pulling moisture out of the air, and that is what turns crunch into chew. This is the "stale" most people mean, and it happens faster in humid weather.
• Oxygen makes chips taste off. Food scientist Fred Caporaso of Chapman University explains that oxygen in the air reacts with the oil in chips and makes them go rancid. That is also why chips don't go stale in the sealed bag: chip makers fill it with nitrogen instead of air.

So the goal is simple: keep air out, keep the chips dry and keep them cool. Every method below does at least one of those.

How to keep chips fresh after opening: 7 ways

1. Close the chip bag without a clip (the fold-and-tuck trick)

No clip? Press as much air out of the bag as you can, then roll or fold the top down tightly toward the chips. To lock it, fold both top corners in to make a triangle, then turn the folded top inside out over them so the bag holds itself shut. Less air in the bag means less moisture and oxygen reaching the chips.

Cost: free. Best for: bags you will finish in a day or two.

2. Use a real bag clip, not a rubber band

A folded bag slowly loosens. A sturdy clip across the full width of the fold holds it shut; a rubber band or a clothespin in the middle leaves gaps at the corners where air gets in.

Cost: a few dollars. Best for: everyday snacking from the pantry.

3. Store chips in an airtight container

A jar or canister with a rubber or silicone seal keeps air and humidity out far better than a clipped bag. Pick a container that the chips nearly fill, since a half-empty container still holds a lot of air. This works well for tortilla chips and chips from a Mexican restaurant, which usually come in bags that don't close at all.

Cost: free if you already have one. Best for: chips you snack on all week, tortilla chips and torn bags.

4. Reseal the chip bag with heat

This is how the bag was closed at the factory. Heat melts the inner layer of the bag so it fuses into a seal, with no gaps for air or moisture to get through. Squeeze out the air, run a sealer along the top, and the bag is closed again.

Our Mini Bag Sealer is made for exactly this. It is a small rechargeable heat sealer with 6 heat settings for thin snack bags, regular plastic bags and thick mylar bags, and a built-in cutter to trim or reopen the bag neatly. It also works on cereal, coffee, frozen vegetables and other food bags.

Best for: big bags, family packs and anyone tired of clips that pop off.

5. Store chips in a cool, dry pantry spot

Heat speeds up the reaction that makes chip oil taste stale. Keep chips away from the stove, the dishwasher, sunny windows and the top of the fridge, which gets warm from the heat the fridge gives off. A pantry shelf or a cabinet away from appliances is ideal.

Cost: free. Best for: every bag, sealed or not.

6. Freeze chips for longer storage

If you bought more than you can eat soon, a tightly sealed bag can go in the freezer. Press out the air and seal it well first. When you take it out, let the bag come to room temperature before opening, so moisture from the air doesn't condense on cold chips.

Cost: free. Best for: bulk buys and party leftovers.

7. Pour a bowl instead of eating from the bag

Every time a bag sits open on the couch, room air and its humidity get in, and hands reaching in add moisture too. Pour what you want into a bowl and close the bag right away. The chips left in the bag stay crisp much longer. At a party, refill a small bowl often instead of setting out the whole bag.

Cost: free. Best for: movie nights, parties and long snack sessions.

Which method is right for you?

• You finish a bag in a day or two: fold, tuck and clip.
• You keep chips around all week: an airtight container or a heat-sealed bag.
• You buy family packs or in bulk: heat-seal the bag, and freeze what you won't eat soon.
• You live somewhere humid: an airtight container or a heat seal; clips and folds won't keep humidity out for long.
• You want to spend nothing: methods 1, 5 and 7.

How to make stale chips crispy again

Soft chips that only absorbed moisture can often be made crunchy again:

• Oven: spread them in a single layer on a baking sheet and warm them at a low heat, around 200–225°F, checking every few minutes.
• Microwave: for a small handful, about 20 seconds on a paper towel–lined plate.
• Air fryer: use the lowest setting for a short time and watch them closely, since thin chips burn quickly.

Let them cool completely before you eat or store them; they crisp up as they cool. One limit: this fixes softness, not rancidity. If chips smell or taste like old oil, the oil has gone off, and heating won't fix it. Throw those out.

Frequently asked questions

How long do chips last after opening?

It depends on how well the bag is closed and how humid your kitchen is. A bag left open or loosely clipped can go soft within a day or two, while a tightly sealed bag or an airtight container keeps chips crisp much longer. For unopened bags, go by the best-by date on the package.

Why don't chips go stale in the sealed bag?

The sealed bag keeps out moisture, and it is usually filled with nitrogen instead of regular air. Nitrogen doesn't react with the chips the way oxygen does, and the extra space cushions them during shipping.

Should you store chips in the fridge?

Not on top of it, where it is warm. Inside the fridge is fine for an opened bag if it is sealed tightly, but for most homes a cool, dry pantry works just as well.

Can you reseal a chip bag with a flat iron, an iron or a lighter?

A flat iron or clothes iron can work, because heat is what seals the bag, but both are hot, hard to control and easy to burn through the bag with. Never use a lighter: an open flame melts the bag unevenly and is a fire risk. A small bag sealer is made for the job and is safer to keep in the kitchen.

How do you keep tortilla chips fresh?

The same rules apply: keep air and moisture out. Tortilla chips often come in paper or thin bags that don't close well, so move them to an airtight container, or into a sealable food bag that you heat-seal.

Tired of soft chips and clips that fall off? Our Mini Bag Sealer reseals snack bags in seconds and ships free in the US. For more ideas, browse our Kitchen Gadgets.

Sources: Chips and Air: Why Your Favorite Snacks Are Always Half Full, NBC; This Popular Chip Storage Spot Might Be Why They Taste Funny, Chowhound; The Easy Oven Hack To Revive Stale Snacks, Food Republic.