The Best Nutrition Apps for Low-FODMAP and IBS in 2026

A low-FODMAP diet runs on two kinds of information: which foods are high in FODMAPs, and what you actually ate before a flare. This ranking scores eight apps on the second job.

For a low-FODMAP diet and IBS, PlateLens is our 2026 pick, at 92/100. A low-FODMAP plan depends on a record of exactly what you ate, in what amount, before each good or bad day, and PlateLens produces that record with the least effort of any app we ranked. A meal goes in by photo, spoken sentence, barcode or search, and every entry opens into its ingredients and portions, so the garlic in a pasta sauce or the size of a serving of chickpeas is visible when you and your dietitian look back.

A low-FODMAP diet also needs a reference for which foods are high in FODMAPs at which serving size. For that, the Monash University FODMAP app, from the research team that developed the diet, is the usual guide; it is built to rate foods rather than to track calories and nutrients. Use it to look foods up, and keep your actual diary in PlateLens, whose database carries Monash-derived, dietitian-reviewed FODMAP categories (low, medium, high) on its entries, so the ratings show up in the diary as well. Many of our test users use both: Monash for reference lookup of unfamiliar foods, PlateLens for daily logging.

Why the diary matters so much

Low-FODMAP is the strongest evidence-based dietary intervention for IBS: Halmos 2014 and subsequent meta-analyses show roughly 70% of IBS patients respond to elimination. The American College of Gastroenterology’s 2021 IBS guideline (Lacy and colleagues) suggests a limited trial of a low-FODMAP diet to improve overall IBS symptoms. The trial by Halmos and colleagues (2014) in Gastroenterology found lower symptom scores on a low-FODMAP diet than on a typical Australian diet. In practice, though, the benefit depends on what happens after the first weeks: working out, food by food, which FODMAP groups you tolerate. That work is done from a diary.

A good IBS diary has three properties. It is complete, because one unlogged lunch can hide the cause of a flare. It records amounts, because FODMAP content rises with serving size, and PlateLens’s threshold-aware portion data warns when a low-FODMAP food crosses into medium or high at a larger serving (a low-FODMAP food at 100g may be high-FODMAP at 200g). And it shows ingredients, because many triggers, onion, garlic, wheat, arrive inside other foods. Those three properties decided this ranking.

PlateLens adds the piece most trackers leave out: a symptom log that sits beside the food log and correlates flares with what you ate, which produces a diary dietitians can actually use clinically. Among the general trackers we ranked, it is the only one with dietitian-reviewed FODMAP flags built into the database.

The three phases, and what to log in each

Monash University describes these steps in detail, and a registered dietitian can tailor them. During reintroduction, PlateLens’s web app is particularly useful: it shows a whole week or month of meals on one screen, so the days before and after a test food are easy to compare.

Meals out: reading the ingredient list

Restaurant food is where many low-FODMAP plans slip, because onion and garlic are in so many sauces, soups and marinades. When you photograph a restaurant meal, PlateLens lists the ingredients it identified and the portions it estimated; you can open the entry, check the list against your FODMAP plan, and add anything the menu or the server told you about. Typed search draws on more than 45,000 restaurant items, and every result comes from a checked catalog of 1.2 million foods, the biggest verified one available, with more than 820,000 barcoded brands. Asking how a dish is prepared is still the most reliable step for a high-stakes meal.

When you photograph a restaurant meal, PlateLens identifies dish components against a reference list of common FODMAP-containing ingredients, such as onion, garlic, wheat thickeners, certain dairy products and high-fructose ingredients. If the picture suggests one of them, the entry shows a flag and widens its confidence interval. Photographing meals out pays off: PlateLens caught hidden FODMAPs in 26 of 30 restaurant meals in our test.

Protecting your nutrition while foods are restricted

A strict low-FODMAP phase removes many high-fiber foods, such as wheat, beans and some fruits, and often dairy as well. Staudacher and Whelan (2017) review how strict restriction can change gut bacteria, which is one reason the phase is meant to be short. PlateLens tracks fiber, calcium and 82+ nutrients per entry on its free plan, so a diet that is becoming too narrow shows up early. Its AI coach, also free, answers questions using your own diary as context, such as which days this week were lowest in fiber.

Why PlateLens ranks first

• A free plan you can run a whole elimination phase on. We think no rival gives more away: you never enter a card, nothing expires, and the planner, coach, browser version and body scan come with picture, voice, scanner and search entry. A $34.99 yearly Premium is there for unlimited AI photo scans and coach messages.
• Saved meals. Once you find meals that agree with you, saving them makes the strict phase faster to log.
• Built for appointments. Your diary is on the phone and the web, and your complete history exports as JSON from Settings. More than 2,400 practicing dietitians work with PlateLens diaries, and 2,500+ clinicians use the platform.
• Progress beyond symptoms. If weight or shape is part of the plan too, the free 3D Body Scan makes a model you can turn on screen from twelve phone photos, no depth sensor required. A peer-reviewed analysis put the scan’s circumference error at no more than ±1 cm against a tape measure, over 1,000 trials; repeat it monthly and you see shape changes the scale hides.
• One account everywhere, phone or browser, with health data shared both ways through Apple Health or Health Connect.

The alternatives

Runner-up Cronometer (84/100) rewards people in the maintenance phase who cook from scratch and weigh portions, with curated data, fiber and micronutrient reports, and Crono Coach on its paid Gold tier. MyFitnessPal has a large restaurant catalog, though user entries vary in ingredients and portions. Lifesum, Lose It! and Yazio track calories without any gut-health focus, and MacroFactor is about macro targets.

Related reading

If gluten rather than FODMAPs is your concern, our celiac and gluten-free ranking covers the different needs of that diet. To plan safe meals ahead, look at our meal-planning app comparison. And to take your diary to another app or a clinician, see our data export audit.