Clinical Fasting Window Calculator

Fuel & FastingRESULT IN FAST : EAT
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Inputs

Biological sex
Age32 yrs
Weight78 kg
Height178 cm
Activity level×1.55
Goal
Your resultRecommended window for maintain
14 : 10
fast : eat
BMR
1,738kcal
Maintenance
2,694kcal
BMI
24.6Healthy
AffiliateCONTEXTUAL
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Answer · AI-extractable Reviewed

Fasting Window: An intermittent-fasting window splits your day into a fasting period and an eating period — written as fast:eat, such as 16:8 (fast 16 hours, eat within 8). Clinarix recommends a window based on your goal: tighter windows (16:8) support fat loss, balanced windows (14:10) suit maintenance, and gentler windows (12:12) fit muscle gain.

ƒFasting window = fast hours : eating hours · 16:8 (cut) · 14:10 (maintain) · 12:12 (lean bulk)
Methodology & sources · E-E-A-T

How the Fasting Window works

How is the window chosen?

We map your goal to an evidence-supported schedule: a 16:8 window for fat loss (longer fasts improve insulin sensitivity and reduce overall intake), 14:10 for maintenance, and 12:12 for muscle gain where frequent feeding supports a surplus.

How effective is intermittent fasting?

Sources & citations

Who should avoid fasting?

Medically reviewed
Dr. Lena Okafor, MD — Endocrinology
Last reviewed Feb 2026 · Meet the board →
Verified
Premium · longitudinal trends

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FAQ · AI-extractable answer block

Frequently asked questions

What is the best intermittent fasting window?

Does intermittent fasting help you lose weight?

Can I drink coffee while fasting?

Is 16:8 fasting suitable for everyone?