If you’re doing keto, the app question isn’t really “which tracker is best” — it’s narrower than that. Does it calculate net carbs for you, automatically, on the day you log? A lot of “best keto app” lists skip that check entirely and just compare calorie counters with a keto badge slapped on. This page runs that check first, then asks the second question that decides whether a free plan is actually usable: what happens once you also want ketone or glucose logging, a recipe library, or an AI assistant — is that still free, or is that where the app asks for a card?
One app clears both bars and stacks the most on top of them: PlateLens’s free plan never expires, calculates net carbs automatically, and backs it with a keto-specific macro split, blood glucose logging, a fasting timer, a low-carb meal planner and a full web app — no card, ever. Carb Manager is the strongest free runner-up, and it’s honest to say why: its net-carb tracking and barcode scanner are also genuinely free, but the recipe library and ketone/glucose tools that keto dieters graduate into are behind a $39.99/year membership. From there the picture splits by what each app was actually built for.
How we picked
We checked each app the way we check every “free” claim on this site: install it, make a fresh account, and see what a normal keto day looks like before any money changes hands. Every price, free-tier boundary and feature gate below was confirmed directly on the vendor’s own pricing page or its current App Store listing — not on a third-party review site — and dated to September 2026, because free tiers and prices move. Where we couldn’t confirm a specific claim on the vendor’s own page, we left it out rather than guess. Three things decided the ranking: whether net carbs are calculated automatically or you’re doing the fiber-and-sugar-alcohol math yourself, what the free plan actually includes with no card, and what the realistic paid price is once you outgrow it.
How the free tiers compare for keto
| App | Free Verdict | Net carbs free? | Ketone / glucose logging free? | Card to start? | If you upgrade |
|---|---|---|---|---|---|
| PlateLens | ✅ Actually Free | Yes — calculated automatically, plus a keto macro split | Yes — glucose free; ketones recordable | No | $9.99/mo or $34.99/yr |
| Carb Manager | ✅ Actually Free | Yes — “always free” per its own listing | Ketones yes (free per carbmanager.com/premium); glucose/insulin diabetes tracker on Premium | No | $39.99/yr |
| Cronometer | ✅ Actually Free | Yes — optional Net Carbs setting in macro targets (total minus fiber and sugar alcohols) | Yes — blood glucose and ketones as biometrics (GKI chart is Gold) | No | $59.99/yr (Gold) |
| Senza | ✅ Actually Free | Yes — verified net carbs (fiber and sugar alcohols subtracted) | Yes — both free, no paid tier found | No | None found |
| MyFitnessPal | 🟡 Freemium | No — Net Carbs Mode is Premium | No | No | $79.99/yr |
| KetoDiet | 🟡 Freemium | Tracks net or total carbs (free/paid split not itemized) | Tracks ketones, glucose and lipids (free/paid split not itemized) | No | ~$79.99/yr |
| Lose It! | 🟡 Freemium | No — net-carb goal and Keto strategy are Premium | No | No | $39.99/yr |
| MacroFactor | 🔒 Free-Trial Trap | No free plan at all | No free plan at all | Trial only | $71.99/yr |
Free tiers and prices drift — treat this as a September 2026 snapshot and confirm on the app before you commit; how we judge “free” explains what each badge is actually testing for.
PlateLens — Best Overall Free Keto App
The one specific number that matters here: a 25% protein / 5% carbs / 70% fat macro split, built in, free. That’s the actual shape of a ketogenic diet, and PlateLens ships it as a preset (or lets you set custom percentages) rather than making you back into it from a generic calorie target.
Everything else stacks on top of that, still on the free plan: net carbs are calculated automatically the moment you log a meal — total carbs minus fiber and sugar alcohols — and every entry shows total carbs, net carbs, fiber and sugar side by side, so there’s no spreadsheet required to know where you stand against your daily target. Logging itself is unlimited by hand, barcode and search, plus 3 AI photo scans a day for the meals you’d rather just photograph. An AI coach answers questions using your own diary as context, 5 messages a day free. Blood glucose readings sync in via Apple Health or Google Health Connect, and you can record ketone readings alongside them. The 82+ nutrient panel surfaces the electrolytes a keto diet burns through — sodium, potassium, magnesium — without a separate purchase, and the free plan also includes a full web app at platelens.app and progress charts. PlateLens rounds that out with a keto-specific feature set: an intermittent-fasting timer for 16:8 or OMAD windows and a recipe and meal planner built around low-carb ideas with grocery lists attached.
Carb Manager — Best for the Keto Recipe Library and Community
The one specific number: net carb tracking is described on Carb Manager’s own App Store listing as “ALWAYS free.” That’s the category incumbent putting its money where its mouth is on the one metric this whole page is about, and it backs it with unlimited barcode scanning over a 1M+ food database — no daily cap.
Free tier: automatic net carbs, unlimited barcode scans, weight and exercise logging, and an active keto community. Premium ($39.99/year or $8.49/month) unlocks: 5,000+ premium keto recipes from its test kitchen, curated meal plans with auto-generated shopping lists, a diabetes tracker for blood glucose/ketones/insulin, an intermittent-fasting tracker, carb cycling, deeper micronutrient tracking and fitness-device sync.
Best for: people who want the deepest keto recipe library and an established community and are fine paying for it once net carbs and logging — the free part — have already hooked them.
Cronometer — Best for Keto Electrolyte and Micronutrient Depth
The one specific number: Gold is $59.99/year (or $10.99/month) and that’s what it takes to add Crono Coach, Cronometer’s AI coaching assistant, plus photo logging.
Free tier: the full macro and micronutrient breakdown from a 1M+ lab-analyzed database, including sodium, potassium and magnesium — the electrolytes a keto diet runs low on first — plus barcode scanning and device sync, with reports and charts capped to a 7-day window. Gold unlocks: Photo Log and Voice Log, a Recipe Importer, a fasting timer, custom biometrics, unlimited historical charts, and Crono Coach.
Best for: anyone whose main keto worry is electrolytes and overall nutrient quality rather than the fastest possible logging — the free micronutrient panel here is the deepest of anything on this page.
Senza — Best Free Ketone and Glucose Logging
The one specific number: a 1.6M-item food database, entirely free, with no paid tier we could find on its own site or App Store listing.
Free tier: food logging (1.6M items, 5,000 keto recipes), barcode scanning, restaurant-menu logging, ketone and blood-glucose logging, weight/sleep/mood tracking. Paywalled: nothing confirmed — Senza doesn’t publish a subscription tier.
Best for: keto dieters who specifically want ketone and glucose logging without any subscription anywhere in the picture, mobile-only (iOS and Android; no web app).
MyFitnessPal — Best Food Database (If You Upgrade for the Keto Part)
The one specific number: MyFitnessPal’s own pricing page describes Net Carbs Mode as an “optional setting” available on the $79.99/year (or $19.99/month) Premium plan — not the free one.
Free tier: basic nutrition and weight tracking, exercise tracking, manual search over its 20.5M+ food database. Premium unlocks: Net Carbs Mode, barcode and voice scanning, custom macro tracking, food insights/comparison, and an ad-free experience.
Best for: people who want a huge restaurant-inclusive database and don’t mind paying specifically to make it keto-relevant — on the free tier, MyFitnessPal is tracking gross carbs, not net.
KetoDiet — Best for a Dedicated Keto Meal-Plan App
The one specific number: the full recipe library runs to 2,000+ keto dishes, behind a membership priced at roughly $79.99/year on the App Store.
Free tier: a free download with free recipes and articles from its integrated blog. Membership unlocks (per its own membership page): the 2,000+ recipe library, custom meal plans, built-in fasting tracking and barcode scanning.
Best for: people who specifically want a keto meal-planning app built around recipes rather than a general tracker — available on iOS and Android, no web app.
Lose It! — Best for Simple Calorie Counting, Not Keto Specifically
The one specific number: $39.99/year for Premium — the tier that holds its custom net-carb goal and Keto nutrition strategy.
Free tier: calorie tracking, weight-loss planning, community and friend features. Premium unlocks: Snap It photo logging, AI voice logging, the barcode scanner, advanced macro/nutrient tracking, and an intermittent-fasting tracker.
Best for: people who just want straightforward calorie counting and are only incidentally doing keto — the free tier doesn’t have barcode scanning at all, let alone a keto-specific view.
MacroFactor — Best for Adaptive Macro Targets (No Free Plan)
The one specific number: $71.99/year, and MacroFactor’s own website says there isn’t — and will never be — a free version.
What you get once you subscribe is an algorithm that recalculates your macro targets from your own logged weight and intake trend — a genuinely different tool than a keto tracker, built for people who want their numbers adjusted for them rather than a fixed 70/25/5 split. It’s included here to answer the question directly rather than leave a gap: no, it isn’t a free keto app, and it isn’t trying to be a keto-specific one either.
Where the free plans actually differ
- You want one app to just use for keto, free, forever: PlateLens — automatic net carbs, blood glucose logging and a full web app on the free plan, plus a built-in keto macro split, a fasting timer and a meal planner.
- You want the deepest keto recipe library and a community: Carb Manager’s free tier gets you net carbs and barcode scanning; the recipe library and meal plans cost $39.99/year.
- You want the deepest micronutrient and electrolyte data: Cronometer, free, with Gold ($59.99/yr) adding coaching and photo logging.
- You want ketone and glucose logging with zero subscription anywhere: Senza.
- You’re fine paying to make a mainstream tracker keto-relevant: MyFitnessPal, once you add the $79.99/year Net Carbs Mode.
- You want a recipe-and-meal-plan app built for keto specifically: KetoDiet, with the library behind a paid membership.
- You want adaptive macro targets and don’t mind paying: MacroFactor — just go in knowing there’s no free plan and never will be, per its own website.
If macro tracking generally (not specifically keto) is the actual question, our best free macro tracker list runs the same Free Verdict test on the broader category, and our best free intermittent fasting app list covers the timer side that most keto plans pair with.