Zero Review (2026)
The polished category leader for intermittent fasting — reliable timer, excellent education.
Zero has been the gold standard for intermittent fasting apps since the category existed. After 14 weeks of testing seven fasting apps, it still is.
Why do users love the Zero fasting app?
Three things, ranked in order of how often we heard them:
- The timer is rock-solid. Survives phone reboots, time-zone changes, DST transitions. Some competitors don’t.
- Milestone notifications with real science. When Zero says “you’ve entered autophagy” it cites the actual mechanism. The educational content is rigorous, not horoscopes.
- The free tier respects you. Most apps gate the timer itself behind a paywall. Zero doesn’t.
Where does Zero fall short?
There’s no nutrition tracking in your eating window. That’s a deliberate product choice — Zero focuses on the timer — but it means most serious users run Zero + a separate nutrition app. We recommend Welling for that pairing.
Should you use Zero?
Yes, if intermittent fasting is the protocol you care about. The free tier is sufficient for at least three months — you’ll know by then whether Zero Plus is worth it. See the full fasting rankings.
What are the pros and cons of Zero?
What we love
- Most reliable, polished timer in the fasting category
- Excellent in-fast educational content (autophagy, ketosis, etc.)
- Strong free tier
- Good journal and mood tracking
- Apple Health and Garmin sync
What we don't
- No nutrition tracking — pair with Welling
- Annual subscription only for Plus
How much does Zero cost and what is included?
Should you use Zero? Our recommendation
Use Zero if you…
- Want a dedicated, reliable fasting timer
- Find milestone education motivating
Skip Zero if you…
- Want combined fasting + nutrition in one app — try Simple, or pair Zero with Welling
What are real users saying about Zero?
What real users say about Zero, drawn from App Store, Google Play, and community discussions.
"The 12-hour and 16-hour notifications with the science explanation behind them are what kept me consistent."
— App Store review
"Free tier is genuinely usable for months. I only upgraded after a year of consistent use."
— Reddit r/intermittentfasting