Do food scanner apps work offline?

A barcode lookup normally needs a connection, because the product record lives on a server, though some apps keep popular products cached for offline use. Reading a photographed ingredient panel can be done on the device, which is how Optimally still returns a result with no network.

Why do two apps give different results for the same barcode?

They may be reading different databases, or the same record at different times. They are also applying different rules to it, which is a separate question from coverage.

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When the scanner cannot find your barcode

Why is my product not in the food scanner app?

The short answer

Usually it means nobody has added that product to the database yet, not that the app is broken. Many scanners, Optimally included, read Open Food Facts, which is crowd-sourced, so coverage follows whoever has been contributing in your country. Three things work. Check you are not hitting a regional barcode difference, because the same product can carry different codes in different markets. Photograph the ingredient panel instead, if the app can read one. Add the product yourself, so it resolves next time for everybody.

Optimally reads the panel on the pack when the barcode is missing or the record has no ingredient list, and falls back to reading it on your device when there is no connection.

Download on the
App StorePaid subscription. Requires iOS.

Why it happens

It is one of the most common complaints in the one- and two-star reviews of food scanner apps, and it is largely structural rather than a fault in any one of them. Open Food Facts, the database behind many scanners, is built by volunteers, and its coverage is strongest in France, where it started, and much thinner in smaller markets.

The gaps tend to be in the same places: supermarket own-brand lines, anything launched in the last few months, regional and local products, and deli items with a store-printed code.

The regional barcode trap

A product sold in several countries can carry a different barcode in each, when it has been registered separately for each market. So the same jar in a British and a German supermarket can be two separate records, one of them well filled in and the other empty.

If an app lets you pick a country, that setting changes which record it prefers, and switching it is worth trying before concluding the product is missing.

Photograph the panel instead

A barcode is a lookup key. The ingredient list on the back of the pack is the actual information, and an app that can read a photograph of it does not need the database entry at all.

This is the reliable answer for own-brand and newly launched products, and it is the only answer for anything without a barcode. It also works for imported products where the local record does not exist.

Add it, so it exists next time

Open Food Facts is a non-profit, open-data project, and adding a product means photographing the front, the ingredients and the nutrition panel in their app or on their site.

That entry is then available to every app that reads Open Food Facts. It is the only one of these three steps that fixes the problem for anyone other than you.

Common questions

Do food scanner apps work offline?: A barcode lookup normally needs a connection, because the product record lives on a server, though some apps keep popular products cached for offline use. Reading a photographed ingredient panel can be done on the device, which is how Optimally still returns a result with no network.
Why do two apps give different results for the same barcode?: They may be reading different databases, or the same record at different times. They are also applying different rules to it, which is a separate question from coverage.

Last reviewed 14 September 2026.