Health & Fitness Calculators (New Zealand)
Explore our suite of free, dietitian-reviewed calculators designed to support your weight management, fitness, and health goals.
- BMI Calculator
- TDEE Calculator
- BMR Calculator
- Macro Calculator
- Calorie Deficit Calculator
- Calorie Calculator
- Body Fat Calculator
- Protein Calculator
- Water Intake Calculator
- Weight Loss Calculator
- Keto Calculator
- Newborn Weight Loss Calculator
- Dog Weight Loss Calculator
- Peptide Dosage Calculator
- Bariatric Surgery Calculator
- Postpartum Weight Loss Calculator
Medically reviewed by Dr. Rekha Kumar, M.D., M.S. — Lead Medical Reviewer · Last reviewed: September 2026 · Updated: 2026-09-15
Evidence & references
This tool is for informational purposes only and is not a substitute for professional medical advice.
Frequently asked questions
Is this calculator free to use?
Yes. Every calculator on Weight Loss Percentage is free, with no sign-up or account required.
How accurate is the result?
Results depend on the accuracy of what you enter and the published formulas the tool uses, which follow standard guidance from national health authorities. Track the trend over weeks rather than relying on a single reading.
How often should I check it?
Check whenever your weight, activity or goals change — for most people once a week is enough to see a reliable trend.
Who reviews the content on this site?
All medical and nutrition content is written and reviewed by Dr. Rekha Kumar, M.D., M.S., our lead medical reviewer, and cites guidance from U.S. federal health sources such as the CDC and NIH.