Understand the method
Mifflin-St Jeor and familiar activity factors, with every result ready to track.
Add a meal or a weigh-in. Your records stay on this device until you choose to sync.
Compare formulas, set a pace and turn energy needs into a practical macro target.
Log meals and weigh-ins. Follow a smoother trend, with no pressure to make every day perfect.
Pro uses complete intake records and trend weight to make measured weekly adjustments.
NASM’s public calorie guide describes the Mifflin-St Jeor equation: 10 × weight in kg + 6.25 × height in cm − 5 × age, with +5 for men or −161 for women. It then applies activity factors from 1.2 to 1.9. This page implements that published calculation method; there is no separate proprietary NASM equation here.
xfit is not affiliated with or endorsed by NASM. This calculator helps you understand the publicly described method and carry your result into a food log. It does not reproduce NASM’s full proprietary calculator or replace individualized assessment. Review the original guide and use your real tracking data to refine the estimate.
One shared calculation engine, with a focus that fits your goal.
No. This is an independent xfit calculator using the public Mifflin-St Jeor method described in NASM’s calorie guide. See the linked source below.
The available factors are 1.2, 1.375, 1.55, 1.725 and 1.9. Choose a factor that reflects your normal activity across the whole week.
