Compare fasting apps
The best intermittent fasting apps, compared
Seven popular fasting apps side by side: what's free, what you pay, what they track and who each one suits
We looked at the fasting apps with the most ratings on the US App Store: Zero, Simple, Fastic, BodyFast, FastEasy and Window, plus our own app, Fasting Tracker. They all time your fasts. Where they differ is what's free, what else they try to do, which devices they run on and what their App Privacy labels say.
At a glance
| Fasting Tracker | Zero | Simple | Fastic | BodyFast | FastEasy | Window | |
|---|---|---|---|---|---|---|---|
| Fasting timer without paying | Yes | Yes | Yes | Yes | Yes | No | Yes |
| Fasting stages | Yes | Yes | Not stated | Yes | Yes | Yes | Not stated |
| Food logging or calorie tracking | No | Yes | Yes | Yes | Yes | Not stated | Yes |
| Apple Watch app | Yes | Yes | Yes | No | No | No | Yes |
| iPad app | Yes | No | No | No | Yes | No | Yes |
| Languages | 31 | 1 (English) | 13 | 11 | 6 | 8 | 10 |
| Data used to track you (App Privacy) | None | None | Yes | Yes | Yes | Yes | Yes |
| "Contains Advertising" (App Store) | Not listed | Not listed | Listed | Listed | Listed | Not listed | Not listed |
| Account needed | No | Not stated | Not stated | Not stated | Optional | Not stated | Not stated |
| Monthly plan | $6.99 | $9.99 | Not stated | $14.99 | $11.99 to $16.99 | $9.99 to $19.99 | $14.99 |
| Yearly plan | $29.99 | $89.99 | Not stated | Not stated | $34.99 to $69.99 | $29.99 | $39.99 to $89.99 |
| Lifetime purchase | $79.99 | Select members only | Not listed | Not listed | Not listed | Not listed | Not listed |
The apps, one by one
Fasting Tracker
Flawless Studio
Best for a free, private fasting timer
Our app. A ring timer with 8 body stages, streaks, badges, weight and water, with nothing to sign up for and no ads. It doesn't log food or count calories.
- 13:11, 14:10, 16:8 and 18:6 free; longer and custom fasts with Pro
- iPhone, iPad, iPhone Duo and Apple Watch, in 31 languages
- Pro from $6.99 a month or $29.99 a year, or $79.99 once for life
- Imports your history from Zero or a spreadsheet
Zero
Zero Longevity Science
Best for a big fasting community
One of the best-known fasting apps, around since 2016. Timers, streaks, weekly trends, expert articles and challenges are free; Zero Plus adds protein and food tracking and more.
- Apple Watch, but no iPad app
- English only
- No data used to track you on its label
- Zero Plus: $9.99 a month or $89.99 a year
Simple
AM Apps / Simple.Life
Best for an AI weight-loss coach
Less a fasting timer than a weight-loss coach: meals, water, weight, activity and an AI assistant, with fasting as one part of it.
- Apple Watch, no iPad app; needs iOS 18.3
- Rated 18+ on the App Store
- Its label lists data used to track you, and "Contains Advertising"
- Pro and Premium listed from $14.99 to $59.99, periods not published
Fastic
Fastic GmbH
Best for food, recipes and steps
Fasting plus food tracking, recipes, a step counter and a community. Without a subscription, its help pages say the fasting timer, water tracker and step counter stay free.
- iPhone only: no Apple Watch or iPad app
- Your account works on one device at a time
- Its label lists data used to track you, and "Contains Advertising"
- Fastic Plus: $14.99 a month
BodyFast
BodyFast GmbH
Best for a guided weekly plan
A free fasting timer and stages, with a paid Coach that changes your plan each week and adds food and calorie tracking.
- iPad and Mac app, but no Apple Watch app
- Can be used without an account
- Its label lists data used to track you, and "Contains Advertising"
- Coach: $11.99 to $16.99 a month, $34.99 to $69.99 a year
FastEasy
Welltech Apps
Best for meal plans with your fast
Fasting with recipes and meal plans. Its listing says you can download it free, but further use requires a subscription.
- iPhone only: no Apple Watch or iPad app
- Its label lists data used to track you
- Premium: $9.99 to $19.99 a month or $29.99 a year
Window
Mosaic / ThrivePort
Best for a timer on every Apple device
A long-running fasting timer with plans and reminders free, and Premium for more, on iPhone, iPad and Apple Watch.
- iPad and Apple Watch apps
- Its label lists data used to track you
- Premium: $14.99 a month, $39.99 to $89.99 a year
How to choose
Five questions before you download
- Decide whether you want a fasting timer or a whole diet app. If you only want to time your fasts, you don't need food logging or a coach.
- Check what's free. Several apps put the core timer up front and charge for the rest; one asks for a subscription to keep using it.
- Read the App Privacy label on the App Store, especially "Data Used to Track You".
- Check your devices: not every app has an Apple Watch or iPad app.
- Compare the monthly and yearly price, and look for a lifetime option if you'd rather not subscribe.
What the App Privacy labels say
Every App Store listing has an App Privacy label, filled in by the developer. "Data Used to Track You" means data linked with other companies' apps, websites or data for advertising, or shared with data brokers. "Contains Advertising" appears in the age-rating details when an app shows ads. Fasting Tracker's label lists no data used to track you; it does link purchase history, identifiers, product interaction and crash data to you, for analytics you can turn off in Settings.
Five of the six other apps list data used to track you, such as purchase history, identifiers or coarse location, and Simple, Fastic and BodyFast list "Contains Advertising". Zero and Fasting Tracker list no data used to track you. Read more about how Fasting Tracker handles your data.
Prices
All seven apps are free to download. Compared by billing period on the US App Store, Fasting Tracker Pro has the lowest monthly price, $6.99, against $9.99 to $19.99 for the others, and shares the lowest yearly price, $29.99, with FastEasy; the others list $34.99 to $89.99 a year. It's also the only one of these apps that offers everyone a one-time lifetime purchase, $79.99.
| App | A month | A year |
|---|---|---|
| Fasting Tracker Pro | $6.99 | $29.99 |
| Zero Plus | $9.99 | $89.99 |
| FastEasy Premium | $9.99 to $19.99 | $29.99 |
| BodyFast Coach | $11.99 to $16.99 | $34.99 to $69.99 |
| Fastic Plus | $14.99 | Not stated |
| Window Premium | $14.99 | $39.99 to $89.99 |
| Simple Pro or Premium | Not stated | Not stated |
Some apps sell cheaper first periods or web-only deals: Zero offers $4.99 for the first month and, on its website, a first year for $39.99, and Window's website offers a year for $19.99. Simple lists prices from $14.99 to $59.99 but doesn't publish which period each one covers. See what's free and what Pro adds.
Questions
What's the best free intermittent fasting app?
If you want the fasting timer itself for free, Fasting Tracker, Zero, BodyFast and Window all include it without paying. Fasting Tracker also includes its 8 stages, four plans from 13:11 to 18:6, streaks, weight, water, widgets and the Apple Watch app in the free version, with no account and no ads.
Which fasting apps don't track you?
On their App Store privacy labels, Fasting Tracker and Zero list no data used to track you. Simple, Fastic, BodyFast, FastEasy and Window each list some.
Which fasting apps work on Apple Watch?
Fasting Tracker, Zero, Simple and Window have Apple Watch apps. Fastic, BodyFast and FastEasy don't list one.
Is there a fasting app for iPad?
Fasting Tracker, BodyFast and Window have iPad apps. Fasting Tracker also has a layout for iPhone Duo, closed and open.
Can I move my fasting history to another app?
Fasting Tracker can import your fasts from Zero's data export, or from any app that exports a spreadsheet or JSON file. See how to switch from Zero.
Which fasting app is the cheapest?
Compared by billing period on the US App Store, Fasting Tracker Pro has the lowest monthly price ($6.99) and shares the lowest yearly price ($29.99) with FastEasy, and it's the only one of these apps with a lifetime purchase for everyone ($79.99). Some apps run cheaper first-period or website deals, and the free versions of Fasting Tracker, Zero, BodyFast and Window cost nothing at all.
Do I need a paid fasting app?
No. A timer, a plan you can keep and water through the fast are what matter most. Paid features such as coaching or longer fasts are extras. Start with how to begin intermittent fasting.
Zero, Simple, Fastic, BodyFast, FastEasy and Window are trademarks of their owners. Fasting Tracker isn't affiliated with, sponsored or endorsed by any of them; their names and icons appear only to identify the apps compared.
A note on health
Fasting Tracker is designed for general wellness and is not a medical device. Fasting is not right for everyone. If you are pregnant, diabetic, have a history of eating disorders or take medication, talk to your doctor first, and before any extended fast.