Free AI Calorie Tracker

Free forever · Open source · Updated September 14, 2026

Fud AI is a free AI calorie tracker for iPhone and Android. Snap a photo, scan a barcode, speak, or type a meal and the AI estimates calories, macros, and detailed nutrients. It is open source under the MIT License, has no subscription, no ads, and no required account, and AI analysis runs on a key you own — so the free part is not a trial.

Download on the App Store Download on Google Play

Is there a free AI calorie tracker? Yes.

Most AI calorie apps put photo scanning behind a subscription because they pay for the AI on your behalf. Fud AI takes a different route: Bring Your Own Key (BYOK). You paste an API key from an AI provider you choose, and the app sends your meal photos or descriptions directly from your phone to that provider. Fud AI never charges for the app itself, and BYOK stays free forever on both platforms.

A free Google Gemini API key takes about a minute to create and covers everyday meal logging for most people.
OpenRouter can be tried on $0 credits — the openrouter/free default routes to a free vision model.
Ollama runs open-weight vision models on your own computer, so requests never leave your network.
Manual entry, barcode lookup via Open Food Facts, saved meals, and native on-device speech recognition work without any AI key at all.

What "free" actually means here

The words "free calorie tracker" cover a lot of business models, so here is exactly how Fud AI works:

No subscription for the core tracker. Logging, nutrients, Coach chat, workouts, widgets, and Health sync are not paywalled.
No ads and no in-app analytics or behavioral tracking.
No required account. There is no Fud AI login and no Fud AI-operated cloud sync of your diary; your data is stored on your device first.
Optional support. The Tip Jar on iOS and Android unlocks nothing; it only supports development.
Optional hosted AI. If you would rather not manage a key, iOS and Android offer optional Plus/Pro hosted AI subscriptions and credit packs. There is no free hosted quota, and choosing BYOK instead is always available and always free.

How the AI calorie scanner works

Fud AI is designed so that logging takes seconds, whichever input you prefer:

Photo: take or import up to 10 food photos for one combined analysis, with an optional note such as "half portion" or "cooked in butter".
Barcode: scan packaged foods and pull nutrition from the public Open Food Facts database.
Voice: describe your meal out loud using native on-device speech or one of six speech-to-text options.
Text, saved meals, and manual entry: type a description, reuse a saved meal, or enter macros directly.
iOS extras: Siri Shortcuts can log food, read today's calories, and log weight; the Share Extension sends photos from other apps straight into Fud AI.

Every result lands on a Review Food screen first. You can rename the food, change grams or a visible unit like slices or cups, unlock and correct calories or nutrients, and preview the day's macro impact with What if? before anything is logged. Learn more about the scanning flow on the AI food scanner page.

More than a calorie counter

Because there is no paywall to work around, everything ships in the same free app:

Calories, protein, carbs, fat, plus 30+ detailed nutrients such as fiber, sugar, sodium, potassium, iron, vitamins, and omega-3 when available.
Personalized calorie and macro targets from published BMR/TDEE equations, with optional Adaptive Goals and Energy Burn Goals.
Weight, body-fat, and optional water tracking; optional intermittent-fasting timer that stays off until you enable it.
A workout diary with sets, reps, weight, RPE, and an 877-exercise library.
An AI Coach tab that can answer questions grounded in your own logged data.
Home Screen and Lock Screen widgets, Apple Watch support on iOS, and Glance widgets on Android.
Optional, permission-controlled sync with Apple Health or Health Connect.

Your data stays on your phone

Fud AI is local-first. Food entries, photos, weight history, and Coach chats live in the app's local storage on your device. API keys are protected in the iOS Keychain or Android EncryptedSharedPreferences and are never sent to us. In BYOK mode, AI requests go straight from your phone to the provider you picked — Fud AI does not sit in the middle. Read the full Privacy Policy for the details, or audit the code yourself on the open-source calorie tracker page.

Frequently asked questions

Is there a free AI calorie tracker?

Yes. Fud AI is a free, open-source AI calorie tracker for iPhone and Android. Bring Your Own Key mode is free forever: you connect a free API key from a provider such as Google Gemini and the app analyzes your meals with it. There is no subscription, no ads, and no required account.

Do I need to pay for an AI key to use Fud AI?

Not necessarily. A free Google Gemini API key takes about a minute to create, OpenRouter's openrouter/free default routes to a free vision model, and Ollama can run open-weight models on your own computer. Manual entry, barcode lookup, and native on-device speech work without any AI key at all.

Is it available on Android as well as iPhone?

Yes. Fud AI is on the App Store for iPhone (iOS 17.6+) and on Google Play for Android (8.0+). Both apps are open source under the MIT License and both support free Bring Your Own Key AI analysis.

How accurate is AI calorie tracking?

AI nutrition estimates are estimates, not lab measurements. Fud AI shows the AI's result on a Review Food screen where you can rename the food, adjust grams or serving units, unlock and correct calories or nutrients, and preview the impact before logging. Barcode lookup uses Open Food Facts product data where available. See the Terms of Service for the full disclaimer on AI estimates.

What is the catch?

There is no hidden upsell in the core tracker. Fud AI is funded by an optional Tip Jar on iOS and Android. Both apps also offer optional Plus/Pro hosted AI plans for people who would rather not manage an API key; those are never required, and BYOK stays free forever.

Get the free AI calorie tracker

Install Fud AI, paste a free API key (or use manual entry and barcodes with no key at all), and start logging. Curious how it compares to subscription apps? Read Fud AI vs Cal AI.