How to Scan a Food Barcode With Your Phone

To scan a product barcode, open the barcode scanner in the app, point your camera at the bars on the package, and wait a second or two for it to scan automatically. Then comes the most important part: choose the serving you actually eat, not the one on the label. In EatSee, barcode scanning is free and doesn't use up AI analyses—even with a free account.

It sounds simple, and usually it is. But a few pitfalls can leave you with numbers in your food diary that don't match what's in your bowl. Let's sort them out.

How to scan a barcode step by step

1. Open the barcode scanner in the app.
2. Allow camera access the first time—without it, your phone can't see anything. If you denied access before, you can enable it in your phone's settings.
3. Fit the barcode inside the frame—about 6 inches from the lens, with the whole barcode visible.
4. Wait for the app to scan the barcode automatically—you don't need to take a photo.
5. Check that the right product came up—the name, flavor, version, and package size.
6. Choose a serving and save.

When scanning several products in a row, such as yogurt, cereal, and milk for breakfast, it takes less time than making a cup of tea.

Can't scan the barcode? Check the lighting and focus

When the scanner gets stuck, one of these little things is usually to blame:

• Glare—foil and shiny packages reflect light. Tilt the product or your phone a few degrees.
• A curved bottle or can—turn it so the barcode faces the camera as flat as possible.
• Too close—the camera can't focus from very close up. Move your phone back and give it a moment.
• A dirty camera lens—a fingerprint on the camera is a classic. Wiping the lens with your sleeve works wonders, seriously.
• A crumpled label—smooth the package with your finger, especially with chips and candy bars.
• Too dark—in low light, turn on the flashlight or move closer to a window.

What does a barcode actually tell you?

A barcode is just a product number. It doesn't contain calories—the app reads the number, looks it up in the product database, and gets the nutrition information from there.

A little fun fact: codes starting with 590 were assigned by the Polish organization GS1. But that tells you where the company registered the code, not where the product was made.

This leads to one practical takeaway: a barcode points to a specific product variant. So it's worth checking the name after scanning—we'll get to that in a moment.

Serving size is where it's easiest to make a mistake

Labels list values per 100 g (or 100 ml), and often for a “serving” defined by the manufacturer, too. The problem is that this serving rarely matches what actually ends up in your bowl.

For example, granola with 450 kcal per 100 g. The serving on the label is 40 g, but a typical bowl is more like 70 g.

That's a difference of 135 kcal in one breakfast. Every day for a week, that adds up to almost 950 kcal—about as much as a hearty lunch.

It's similar with drinks. Juice with 45 kcal per 100 ml may seem harmless, but a 500 ml bottle comes to about 225 kcal. If you're not sure how much you're having, weigh it once or check out our guide to estimating a serving without a scale.

Check the product variant

The same manufacturer may have several versions on the shelf that look almost identical: regular and light, vanilla and chocolate, small and large cups. Products on the same shelf can also differ more than you'd think—a plain yogurt and Greek yogurt sit side by side, but Greek yogurt usually has about twice as many calories.

After scanning, check that the name and variant match. If they don't, scan it again or add the product another way.

What if a product isn't in the database?

The EatSee database includes products available in Polish stores, but you may come across a new product or an imported product. In that case:

1. Scan it again—sometimes the barcode is misread.
2. Take a photo of the label—AI will analyze the nutrition facts table and provide calories and macros.
3. Say or write in one sentence what it is and how much you're eating, such as “plain yogurt, 2%, 150 g”.
4. Add the product manually by copying the values from the nutrition table on the package.

Loose products: cold cuts, cheese, and bread

Stickers from deli counters or bakeries usually have the store’s internal codes. These contain the price or weight, not a product from the database, so the scanner usually won’t recognize them.

For these products, it’s quickest to take a photo of your sandwich or say in one sentence what you’re eating, for example, “three slices of ham and two slices of cheese.” Learn more about this method in our guide to logging a meal by voice.

Barcode or photo?

Barcodes work best for anything you eat straight from the package: yogurt, bars, cereal, drinks, and ready meals. The information comes from the label, so it’s hard to get a more accurate result.

Photos work best for meals made up of several items—a plated meal, sandwiches, or a salad. We explain how to use this feature in our article on whether counting calories from a meal photo works. You don’t have to stick to one method—you can log everything in the same food diary.

This article is for informational purposes only and does not replace advice from a doctor or dietitian. Written by the EatSee editorial team. Editorial policy.