MyFitnessPal vs Deficit: Comparison

Who is this comparison for?

For someone deciding between the default mass-market tracker (MyFitnessPal) and a narrower, athlete-focused alternative (Deficit). It assumes you train, you already log food or are willing to, and you care whether the calorie math fits a muscular body. If you want the largest possible food database and a free tier, that answer is short and it's MyFitnessPal. If you want structured cuts anchored on body composition, read on.

MyFitnessPal vs Deficit at a glance

MyFitnessPal details accurate as of 2026; its plans and features change often, so check the App Store listing for current pricing. Every Deficit plan includes a 7-day free trial.

Where is MyFitnessPal the better choice?

MyFitnessPal has been the default calorie tracker for two decades, and for good reason. Three real cases where it's the right pick:

If you want the largest food database

MyFitnessPal's database runs into the tens of millions of entries, built up over twenty years of users adding foods. For obscure international items, specific restaurant meals, and packaged products from anywhere in the world, it finds a match more often than any smaller app. If your meals are varied and you hate not finding an entry, this is the strongest reason to stay.

If you want a free tier or you're on Android

MyFitnessPal has a genuine free tier, ad-supported, and runs on iOS, Android, and the web. Deficit is paid-only and iOS-only. If you won't pay for a tracker, or you live in the Android ecosystem, or you log on a laptop, MyFitnessPal is the only one of the two that fits.

If you want a mature app with every integration

Twenty years of development means MyFitnessPal connects to almost everything: fitness wearables, recipe importers, restaurant menus, and a large community. Deficit launched in 2026 with a focused feature set and none of that surface area yet. For breadth of integrations, MyFitnessPal wins by history.

Where is Deficit the better choice?

If your calorie target should adjust to your body

This is the largest real gap between the two. MyFitnessPal sets a calorie goal once at signup and leaves it there until you manually recalculate. If your metabolism shifts as you lose weight, the number stops describing you and you don't find out until the scale stalls. Deficit re-estimates your target every week from your logged weight trend, so the goal tracks your actual body instead of a day-one guess.

If you want a calorie base built for trained bodies

MyFitnessPal uses Mifflin-St Jeor, which reads total weight, height, age, and sex. It works for the general population and reads low for muscular people. Deficit uses Cunningham, which takes lean body mass directly. For trained populations Cunningham predicts resting metabolic rate within about 10% of measured values, while Mifflin-St Jeor underestimates trained subjects by 5 to 15%.

Concretely: a lifter at 80 kg and 12% body fat has 70.4 kg of lean mass. Cunningham gives a BMR of 2,049 kcal; Mifflin-St Jeor (at 178 cm, 30 years, male) gives 1,768 kcal. That 280 kcal per day gap, held over an 8-week cut, is roughly 2 kg of lean mass you didn't need to lose. The lean body mass calculator shows the full chain, and why Cunningham fits athletes explains the equation.

If you cut in cycles, not indefinitely

MyFitnessPal is open-ended logging: there's no phase, no end date, no built-in stopping point. Deficit assumes a cut of 4 to 12 weeks with a defined finish, then a maintenance phase before the next one. Cuts past 12 weeks show falling compliance and rising metabolic adaptation, and 8 weeks is roughly where the trade-off peaks. If your past attempts dragged on and fell apart, the missing piece was the stopping rule. The case against dieting forever covers why.

If you want no ads, no account, and on-device data

MyFitnessPal's free tier shows ads, requires a cloud account, and stores your log on its servers. Deficit has no ads, no account, no email signup, and keeps everything on your device. If your phone goes offline, it keeps working. For people who dislike ads in a health app or don't want their food log on someone's server, this is a clear split.

The real differences in detail

Static goal vs weekly adjustment

MyFitnessPal's calorie goal is a fixed number until you change it. It doesn't watch your weight trend and adapt on its own. Deficit runs a weekly check-in: it reads your smoothed weight change, compares it to the target rate, and nudges calories to keep you on pace. Over an 8-week cut, that's the difference between a target that drifts out of date and one that stays current. The weekly check-in walks through the loop.

How they calculate calories: Cunningham vs Mifflin-St Jeor

MyFitnessPal: Mifflin-St Jeor (men)
RMR = 10×weight(kg) + 6.25×height(cm) − 5×age + 5
goal = RMR × activity − chosen deficit (set once)

Deficit: Cunningham
BMR = 500 + 22 × LBM(kg)
TDEE = BMR × PAL × TEF, re-estimated weekly

Cunningham skips height and age and reads lean mass directly, which is the physiological signal those proxies stand in for. The how Deficit works page shows every formula with its sources.

How they handle protein: percentage vs lean mass

MyFitnessPal sets protein as a percentage of calories by default, with gram targets available on Premium. Deficit anchors protein to lean body mass at 2.2 g/kg LBM. A percentage target drifts with your calorie total; a lean-mass target stays fixed to the tissue you're protecting. The protein anchor question covers why lean mass is the better reference on a cut.

How they handle data: on-device vs cloud account

MyFitnessPal requires an account and syncs to its servers, which makes multi-device logging easy and supports its social features. Deficit keeps data on-device, so there's no signup and nothing leaves your phone, at the cost of no multi-device sync. Neither choice is wrong; they serve different priorities.

Things that are roughly the same

The gaps above are real, but a lot of the daily experience overlaps.

• Core logging. Both support search, barcode scanning, recents, and favorites. After a few days most meals are one or two taps in either app.
• Apple Health. Both read steps, workouts, and weight from HealthKit on iOS.
• Weight-trend smoothing. Both surface a smoothed weight trend rather than reacting to single-day scale noise.
• Macro tracking. Both track protein, carbs, and fat against a target, not calories alone.

Pricing

MyFitnessPal is cheaper if the free tier covers your needs, and its Premium runs higher than Deficit's annual plan. Deficit is paid-only with no ads and no feature gates: you get the whole app from day one. MyFitnessPal's pricing changes often, so confirm current numbers on the App Store.

Frequently Asked Questions

Other Deficit comparisons

Weighing more options? See how Deficit compares to MacroFactor, Cronometer, and Carbon Diet Coach, or read how Deficit works under the hood.