Zero - Fasting Tracker

Reach your health goals with the #1 fasting app.

Zero is a beautifully designed tracker used for intermittent, circadian rhythm, and custom extended fasting. As the largest app-based fasting community in the world, Zero makes it simple for you to harness the power of fasting to improve your health.

Zero’s advisory team includes some of the world’s leading doctors and researchers, including our Chief Medical Officer Dr. Peter Attia, who guides our fasting protocols and content creation.

Zero makes fasting simple:

• A beautiful, thoughtful design makes it simple to start fasting

• Earn badges to celebrate your fasting milestones and stay motivated

• Set a weight goal and track your progress

• Visualize your fasting progress over time

• Reflect on your fasting experience with the fasting journal

• Weekly articles created by our expert content team to keep you informed and motivated

• Stay accountable with group fasts and special events

Quickly start your fast based on science from leading doctors and researchers.

• 16 hour fast, known as the 16:8 Intermittent Fast, used by celebrities like Hugh Jackman and Halle Bailey when preparing for blockbuster films

• Circadian Rhythm Fast, based on research by Dr. Satchin Panda (Salk Institute), this 13 hour fast starts at or before sunset to align your eating window with your body’s clock. Zero automatically calculates the daily sunset time based on your location

• 18 hour fast, known as the 18:6 for more advanced fasters

• Other popular fasts include OMAD (one meal a day), 20:4 fast and custom fasting up to 7 days

Choose your favorite fasting protocol and Zero will track your progress on your iPhone or Apple Watch with Apple Health integration to sync your weight, resting heart rate and sleep.

Join the largest fasting community in the world!