Intermittent Fasting Calculator – Eating and Fasting Windows
Calculate your eating window and fasting window for any IF protocol.
❤️ Health📐
Wake time (24hr, e.g. 7)
Protocol
Please enter valid values.
Formula & Reference
| Variable | Formula | Units |
|---|---|---|
| Intermittent Fasting Calculator – Eating and Fasting Windows | result |
Step-by-Step Examples
Example 1
16:8, wake at 7am
- Fast until 8am | Eat 8am-4pm | Fast 4pm-8am
✓ Eat 8am-4pm
Example 2
18:6, wake at 7am
- Fast until 9am | Eat 9am-3pm
✓ Eat 9am-3pm
Example 3
OMAD, wake at 6am
- 1 hour eating window | Fast 23 hours
✓ 1hr eating window
Real-World Applications
IF Dieters
Know your daily eating and fasting schedule.
Health Trackers
Track fasting consistency.
Gym-Goers
Plan nutrition around workouts.
Clinicians
Advise on fasting protocols.
Common Mistakes to Avoid
⚠️
IF controls when, not what
Fasting window doesn't fix poor food choices during eating window.
⚠️
No water during fast (wrong)
Water, black coffee, and plain tea are allowed. Staying hydrated is important.
Frequently Asked Questions
Does IF work for weight loss? ▾
Yes — by limiting eating window, most people reduce total calorie intake. Still requires caloric deficit.
Best protocol for beginners? ▾
Start with 16:8. Most sustainable. Extend window gradually if desired.
Exercise while fasting? ▾
Yes — many train fasted. Eat protein within 2hrs post-training for muscle recovery.