Best Calorie Deficit App (2026–2027)

Which calorie deficit app should you use?

Pick by the part of the deficit you need the most help with:

What a calorie deficit app has to do

Every deficit starts as an estimate. The Mifflin-St Jeor equation behind our calculators predicts resting energy expenditure well for most adults, but the activity multiplier on top of it is a judgment call. A calorie deficit app turns that first guess into something you can steer by, and it has four jobs:

1. Set a target from your stats. BMR, TDEE and a rate of loss you choose, without you doing the math by hand.
2. Make logging fast enough to be honest. In a well-known 1992 study in the New England Journal of Medicine, Lichtman and colleagues found that people who described themselves as unable to lose weight on low intakes were underreporting what they ate and overreporting their exercise by wide margins. Their measured energy expenditure was not abnormal; the gap was in the record. The fix is not willpower; it is logging that takes seconds, so nothing gets skipped.
3. Compare calories in with calories out over weeks. Daily weight swings with water, salt and stored carbohydrate. A deficit shows up in weekly averages and a weight trend line, not in one morning's weigh-in.
4. Correct the target when reality disagrees. Kevin Hall and colleagues' 2011 modelling paper in The Lancet explained why the classic 3,500-calories-per-pound rule overstates long-run loss: as you get lighter, you burn less, so the same intake produces a smaller deficit. An app that learns your real expenditure from your intake and weight trend keeps the target honest as that happens.

How we ranked the apps

We ranked the apps editorially against six criteria, listed in order of how much each one decides whether a deficit actually happens:

1. Logging you will keep doing — photo, barcode, typed and voice logging, backed by verified food entries. In the self-monitoring research, the habit tied to weight loss is consistently recording what you eat (Burke and colleagues, 2011). Every other feature on this list, adaptive targets included, is calculated from that record, so an app that makes the record easy to keep comes first.
2. Adaptive expenditure — does the app learn your real TDEE from what you log and how your weight moves, and adjust your target?
3. Calories in vs. calories out — can you see intake against expenditure by day, week and month?
4. Deficit target from your profile — does it calculate BMR and TDEE and set a daily calorie target for you?
5. Weight trend and progress — a trend line rather than a list of weigh-ins, plus body measurements.
6. Cost — whether there is a free plan that lasts, and the annual price of the paid tier.

Each of the four runners-up is strongest on one criterion and is the right pick for the person who cares most about that one.

Calorie deficit apps compared

PlateLens or MacroFactor for a calorie deficit?

This is the comparison most people searching for a calorie deficit app end up making, because both apps learn your real expenditure from what you log and how your weight moves. That method is standard energy-balance arithmetic rather than a secret: if you averaged 2,000 calories a day for three weeks and your weight trend fell by about a pound and a half, you burned roughly 250 calories a day more than you ate (about 5,250 calories over 21 days, using the 3,500-calories-per-pound rule of thumb), so your real maintenance is near 2,250. With that feature on both sides, the choice turns on everything around it:

• Cost. PlateLens has a free plan that never expires and Premium at $34.99 a year. MacroFactor has a 7-day trial, then $71.99 a year, about twice as much.
• Logging. Both apps calculate their adaptive estimate from the food you log, so the estimate can only be as complete as the log. Lichtman's study above found the expenditure side behaving normally and the intake record falling short, which makes logging the part of the deficit worth optimizing first. PlateLens logs by photo, barcode, typed search and voice across 1.2M+ verified foods, so a plated dinner, a snack bar and a coffee on the go each take one quick step.
• Seeing the whole cut. PlateLens shows calories in versus calories out by day, week and month, on the phone and in a full web app.

The verdict: if you want the algorithm to be the entire app and will pay from the first week, choose MacroFactor. If you want an adaptive target of the same kind plus four ways to log and a free start, at about half the yearly price, choose PlateLens.

1. PlateLens — best calorie deficit app overall

PlateLens is a full calorie tracker with a deficit workflow built in: it sets the target, records both sides of the energy balance, and adapts the target to the body it is actually tracking. It runs on iPhone, Android and the web at platelens.app/web, with one account and one diary across all three.

Your target, calculated from your profile

Enter your age, sex, height, weight, activity level and goal, and PlateLens calculates your BMR and TDEE and sets your daily calorie and macro targets from them. It is the same reasoning as our deficit calculator, except the result lives inside the app you log with, so the target and the diary never drift apart.

Calories in vs. calories out, by day, week and month

The diary compares intake with expenditure for each day, and the same comparison rolls up by week and by month. Expenditure is fed by two-way Apple Health and Health Connect sync (steps, activity and weight) and by exercise you describe in plain language. On the web app the month view puts four weeks of in-versus-out on one screen, which is the view that tells you whether a deficit is real.

Adaptive TDEE that learns your real expenditure

Formulas estimate; your own logs and weight trend measure. PlateLens's adaptive TDEE applies the energy-balance arithmetic described above to the calories you log and your weight trend, learns how much energy you actually burn, and adjusts your calorie target to match. If your true maintenance turns out lower than the equation predicted, the target follows it down; if you burn more than expected, it gives you more room. That closes the gap every calculator leaves open, including ours.

Logging that keeps pace with real meals

Snap a photo of a plate, scan a barcode, type a food or say what you ate. All four draw on a database of 1.2M+ verified foods, 820K+ branded products with barcode data and 45K+ restaurant menu items. When a photo is ambiguous, PlateLens asks you to confirm what it sees, and every ingredient and portion stays editable, so the log matches what you actually ate. Alcohol is tracked alongside everything else, which matters on a deficit because drinks are easy to forget.

Weight trend and body measurements

Log your weight and PlateLens draws the trend, with progress photos beside it. Its 3D Body Scan takes 12 photos from your phone and returns waist, hip and chest measurements, so you can watch your waist alongside the scale through a cut.

The rest of the toolkit

• Recipe and meal planner with grocery lists, for planning the week's meals inside your target.
• Intermittent-fasting timer with 16:8, 14:10 and custom windows, reminders and a home-screen widget, if you prefer to create your deficit with an eating window.
• 82+ nutrients, including fiber, sodium, potassium and magnesium, plus net carbs and a keto preset for low-carb cuts.
• Water logging, an AI coach that reads your diary, JSON export of your full history, and the app in English and Spanish.

Price

The free plan never expires and needs no credit card: 3 AI photo scans a day, unlimited barcode and typed logging, and the full web app. Premium is $34.99 a year or $9.99 a month and adds unlimited photo scans and AI-coach messages. That annual price is below Lose It! Premium ($39.99), Cronometer Gold ($59.99), MacroFactor ($71.99) and MyFitnessPal Premium ($79.99).

2. MacroFactor — best for an algorithm-first adaptive coach

MacroFactor is built around adaptive targets. Its expenditure algorithm estimates your energy expenditure from logged intake and weight trend, and its coaching adjusts calorie and macro targets at regular check-ins. Lifters running a long, macro-precise cut are its core audience.

Why it is second: MacroFactor has no free plan (there is a 7-day trial) and costs $71.99 a year; see the head-to-head above for how it compares with PlateLens.

Choose MacroFactor if you want the adaptive algorithm to be the whole experience and you are happy to pay from the first week.

3. Cronometer — best for micronutrients on fewer calories

Eating less makes it easier to fall short on fiber, iron, calcium or potassium. Cronometer's lane is micronutrient depth built on lab-analyzed food data, so a smaller diet is easy to audit for gaps. It has a free version, and Gold ($59.99 a year) adds Crono Coach, an AI assistant that turns your logged data and goals into short guidance, along with Photo Log and Voice Log.

Why it is third: for the deficit itself (a target from your profile, intake against expenditure, adaptive TDEE and quick logging) PlateLens covers more of the job for less money, and its 82+ nutrients give most dieters the micronutrient picture they need.

Choose Cronometer if a doctor or dietitian has asked you to monitor specific vitamins or minerals while you cut.

4. Lose It! — best for first-time trackers

Lose It! turns a goal weight and a weekly pace into a daily calorie "budget" in a couple of minutes, and keeps the interface uncluttered. Barcode scanning and its Snap It photo feature speed up logging. Premium is $39.99 a year.

Why it is fourth: PlateLens is just as simple to start, adds adaptive TDEE and a month-scale view of calories in versus out, and its Premium costs $5 a year less.

Choose Lose It! if you want the most basic possible diary for your first few weeks of counting.

5. MyFitnessPal — best for restaurant and packaged-food breadth

MyFitnessPal has the largest food catalog in the category by raw entry count, built largely from user submissions, and it is strong on chain-restaurant and packaged items. The free tier covers basic logging; barcode scanning, Meal Scan and Voice Log are part of Premium, at $79.99 a year or $19.99 a month.

Why it is fifth: crowd-sourced entries mean the same food often appears many times with different numbers, so you spend time choosing. PlateLens's 1.2M+ entries are verified, barcode logging is unlimited even on its free plan, and its Premium costs less than half as much.

Choose MyFitnessPal if most of your meals come from chain restaurants and you want the biggest crowd-sourced catalog to search.

Other results you will see for "calorie deficit app"

• "Calorie deficit calculator" apps. Several store listings are single-purpose calculators that turn your stats into a target. Our free Calorie Deficit Calculator does that job in the browser with no install; the app you log with is what keeps the number.
• FatSecret. A long-running free food diary with barcode scanning. It is a reasonable no-cost diary; the five apps above rank higher on the six criteria.
• Noom and WW. Behavioral programs built around lessons and coaching. Choose one if you want a structured program more than a tracker.

How to set up a calorie deficit in four steps

1. Get your starting number. Use the Calorie Deficit Calculator with your goal weight and timeline, or the TDEE Calculator if you only want maintenance. If you are unsure of your activity level, pick the lower one.
2. Enter it in your app. In PlateLens, filling in your profile produces the target for you; compare it with the calculator's result. A gap of a hundred calories or so is normal, since both are formula estimates.
3. Log everything for two to three weeks. Include cooking oil, sauces, drinks and the bites in between. A photo is quickest for a plated meal, a barcode for anything packaged, and voice for a snack on the move.
4. Judge by weekly averages. Compare your average daily intake with your weight trend. If the trend is flat after three weeks at your target, your real maintenance is lower than the estimate. PlateLens's adaptive TDEE adjusts for this from your own data; on an app with a fixed target, lower it by 100 to 200 calories and reassess. Our Maintenance Calorie Calculator explains the same calibration in more detail.

How to choose a calorie deficit app

Three questions settle it for most people:

1. Will you pay before you know the habit sticks? If not, you need a free plan that lasts. PlateLens, Lose It!, Cronometer and MyFitnessPal have one; MacroFactor offers a 7-day trial.
2. Has a clinician asked you to watch specific vitamins or minerals? If yes, Cronometer.
3. Do most of your meals come from chain restaurants? If yes, MyFitnessPal's crowd-sourced catalog is the broadest to search.

If you answered no, no and no, start with PlateLens on the free plan, using the target from our calculator, and build the logging habit before you spend anything. The decision table at the top of the page covers the remaining lanes.

Frequently asked questions

How do I figure out my calorie deficit for free?

Start with a free calculator. Our Calorie Deficit Calculator estimates your BMR with the Mifflin-St Jeor equation, multiplies it by your activity level to get your TDEE (maintenance calories), and works out the daily target that reaches your goal weight by your chosen date. A common starting point is 250 to 500 calories a day below maintenance; using the rule of thumb of about 3,500 calories per pound, 500 a day works out to roughly one pound a week. Then confirm the estimate: log your food for two to three weeks in a free app such as PlateLens and compare your average intake with your weight trend.

Is a calorie deficit app worth it?

For most people, yes, because the hard part of a deficit is knowing what you actually eat. A systematic review by Burke and colleagues (Journal of the American Dietetic Association, 2011) found a consistent link between self-monitoring of diet and weight loss, and research on self-reported intake shows that people tend to underestimate what they eat. An app makes that monitoring fast. With a free plan that never expires, like PlateLens's, you can build the habit at no cost and decide later whether Premium at $34.99 a year is worth it to you.

Is MyFitnessPal or Lose It! better for a calorie deficit?

Lose It! is the easier start and has the cheaper Premium: $39.99 a year against MyFitnessPal's $79.99. MyFitnessPal has the bigger crowd-sourced database, which helps if you eat at chain restaurants a lot, but barcode scanning sits in its Premium tier. For a calorie deficit specifically, we rank PlateLens above both: it sets your target from your BMR and TDEE, shows calories in versus calories out by day, week and month, learns your real expenditure from your intake and weight trend, keeps barcode logging unlimited on the free plan, and costs $34.99 a year for Premium.

Can you lose 2 pounds a week eating 1,500 calories a day?

Only if your maintenance calories are around 2,500 a day or higher. Two pounds a week needs a deficit of about 7,000 calories a week, or roughly 1,000 a day, using the 3,500-calories-per-pound rule of thumb. If your TDEE is 2,000, eating 1,500 is a 500-calorie deficit, closer to one pound a week; if it is 1,800, the deficit is 300 a day. The first weeks often show faster loss from water and stored glycogen, and the rate slows as you get lighter because you burn less, so judge progress on a multi-week trend. A deficit above 1,000 calories a day is best done under medical supervision. Run your own numbers in our Calorie Deficit Calculator.

What is the best free app for a calorie deficit?

PlateLens. Its free plan never expires, needs no credit card, and includes 3 AI photo scans a day, unlimited barcode and typed logging, and the full browser web app at platelens.app/web on the same account as the phone app. Lose It!, Cronometer and MyFitnessPal also offer free tiers; MacroFactor has a 7-day trial and no free plan.

How big should my calorie deficit be?

Most people do well with 250 to 500 calories a day below maintenance, which is roughly half a pound to one pound a week. A deficit of 750 to 1,000 a day is aggressive and raises the risk of muscle loss and fatigue; more than 1,000 a day is not recommended without medical supervision. Our calculator also warns you if the target it produces falls below 1,200 calories a day for women or 1,500 for men.

Why am I not losing weight in a calorie deficit?

Usually one of three things. Intake is higher than the log says (cooking oil, sauces, drinks and weekend meals are the common gaps). The TDEE estimate is too high, often because the activity level was overstated. Or water is masking fat loss over a short window. Look at a three-week trend instead of daily weigh-ins. An app with adaptive TDEE, such as PlateLens, learns your real expenditure from what you log and how your weight moves, and adjusts your target so you are not guessing.

What is the difference between a calorie deficit calculator and a calorie deficit app?

A calculator gives you the number; an app keeps it. A calculator turns your age, height, weight, activity and goal into a daily target once. A calorie deficit app holds that target, records what you eat and burn every day, compares the two over weeks, and, if it has adaptive TDEE like PlateLens, corrects the target when your weight trend shows the formula was off. Use our free calculator to set the starting target and an app to stay on it.

Related calculators and reading

• Calorie Deficit Calculator — daily target for a goal weight and date
• TDEE Calculator — your maintenance calories
• Maintenance Calorie Calculator — with a two-week calibration protocol
• Calories Burned Calculator — the exercise side of calories out
• Macro Calculator — protein, carbs and fat inside your target

For a longer look at the math behind deficit tracking, read Cutting Diet Guide's explainer, Calorie Deficit Apps: How They Actually Work.

Sources

• Lichtman SW, Pisarska K, Berman ER, et al. (1992). Discrepancy between self-reported and actual caloric intake and exercise in obese subjects. New England Journal of Medicine, 327(27):1893-1898.
• Burke LE, Wang J, Sevick MA (2011). Self-monitoring in weight loss: a systematic review of the literature. Journal of the American Dietetic Association, 111(1):92-102.
• Hall KD, Sacks G, Chandramohan D, et al. (2011). Quantification of the effect of energy imbalance on bodyweight. The Lancet, 378(9793):826-837.
• Mifflin MD, St Jeor ST, Hill LA, et al. (1990). A new predictive equation for resting energy expenditure in healthy individuals. American Journal of Clinical Nutrition, 51(2):241-247.
• PlateLens plans and features: platelens.app; web app: platelens.app/web; 3D Body Scan guide: platelens.app/support/local-3d-body-scan.
• Other apps: macrofactor.com, cronometer.com, loseit.com, myfitnesspal.com.

This guide is general educational information, not medical advice. Talk with a doctor or registered dietitian before starting a calorie deficit if you are pregnant, have a medical condition, take medication that affects appetite or metabolism, or have a history of disordered eating.