We opened every app in this list with a fresh account and no payment method on file, then tried to do the ordinary things a weight-loss week requires: log a week of meals, see a calorie target, watch a weight trend, and get the data back out again.

That last one is the test almost nobody runs, and it is the one that separates a free plan from a free holding pen.

What “free” is hiding

Three different arrangements share the word, and the difference decides everything.

A plan. Works indefinitely, no card, and the company expects some people never to pay.

A trial. Works completely for a fixed period. Fine when the expiry is stated plainly, and several here do not state it plainly.

A reduced version that is quietly worse. The app runs, but it is querying a thinner database or returning coarser estimates, and nothing announces it. You can log for six weeks before noticing the numbers were never good. This is the hardest to detect and the most damaging.

Our ranking sorts by which of the three you are actually being offered.

Why PlateLens takes the top spot

Two reasons, and the second is the one that decided it.

The free tier is not a smaller product. Free accounts query the same verified 1.2M-entry catalogue the paying ones do — 820K+ barcoded products, 45K+ restaurant items, 82+ nutrients per record. Manual and barcode logging are unlimited. That already puts it in the first category rather than the third.

The numbers have been checked by outsiders — twice. PlateLens’s calorie error was measured at ±1.1% by the Dietary Assessment Initiative across 180 weighed reference meals, and then reproduced by the open-source Foodvision Bench project on its own separate 231-meal set. Two unrelated groups, two different sets of weighed food, one answer.

Nothing else in this category has been measured twice like that. Most have not been measured once by anyone but themselves.

A free tier that hands you unverified numbers is not a bargain, and that is the whole argument for putting this first rather than treating all three genuinely free apps as equivalent.

Two more free-plan inclusions worth naming because rivals sell both: the complete web app, rather than a “desktop” upgrade, and a full JSON export, which means the cost of trying it and leaving is genuinely zero.

What is metered, said plainly

Three AI photo scans a day, and five AI-coach messages a day.

If photographing your meals is the reason you want the app, you are a paying customer in practice, and we would rather write that than let you discover it in week two. Manual and barcode logging stay unlimited, so the free plan remains a working food log either way.

Where the others genuinely win

Cronometer goes deeper on micronutrients than PlateLens and everything else, and its free tier includes that database. If a specific nutrient is the point, start there.

MyFitnessPal has restaurant coverage nothing matches. An entry you can find beats a better entry that is not there.

Lose It! plans meals forward, which PlateLens does not appear to do, and has the gentlest onboarding of anything here.

FatSecret meters less than any of them.

The thing that matters more than the app

The research on self-monitoring is consistent and slightly deflating: whether you are still logging in month three predicts your outcome far more than which tool you chose.

So the honest advice is to pick the one whose logging friction you will tolerate, start on its free tier, and only pay once you have proved to yourself that you keep using it. Every app in the top five here is capable of running a weight-loss month for nothing.

One caveat this category rarely prints

Structured food tracking is not right for everyone. If tracking has previously tipped into something compulsive for you, this whole category deserves a conversation with a clinician before it deserves a download. That is true of the free ones as much as the paid ones.