BAC Calculator
Estimate blood alcohol content based on drinks consumed, weight, and time.
BAC Calculator
Estimate blood alcohol content based on drinks consumed, weight, and time.
Body Mass Index (BMI)
ℹ️ Underweight < 18.5 | Normal 18.5–24.9 | Overweight 25–29.9 | Obese ≥ 30
Disclaimer
Results provided by this calculator are for informational and educational purposes only. They are based on the values you enter and standard formulas, and should not be considered financial, medical, legal, or professional advice. Always consult a qualified professional before making important decisions based on these results. Roughtools makes no warranties regarding the accuracy or completeness of these calculations for your specific situation.
Frequently Asked Questions
Pro Tips
BMI does not distinguish between muscle and fat — athletes routinely register as "overweight." Use BMI alongside waist circumference and body fat percentage for a complete picture.
Waist-to-height ratio (waist ÷ height) below 0.5 is a strong predictor of metabolic health — often more useful than BMI for assessing cardiovascular risk.
Asian populations have higher metabolic risk at lower BMI values. Some clinicians use BMI ≥23 as overweight for Asian adults, not the WHO standard of 25.
Track your BMI trend over months, not as a single snapshot. A consistent downward trend matters far more than hitting a specific number on any given day.
When to Use This Calculator
Calculate your BMI as part of your annual health self-assessment alongside blood pressure and cholesterol.
Find the BMI-normal weight range for your height to set a realistic, medically-recognised target weight.
Check whether BMI is in the healthy range before conceiving — optimal range reduces pregnancy complications.
Monitor BMI monthly during a training program — though note athletes may show high BMI despite low body fat.
Calculate your BMI in advance so you can have an informed conversation about your weight with your healthcare provider.
About the BAC Calculator
The BAC Calculator estimates blood alcohol concentration using the Widmark formula, accounting for body weight, sex, number of standard drinks, and time elapsed since drinking began. It is an educational estimation tool to help people understand how alcohol affects the body. Results are approximations — actual BAC varies based on food intake, metabolism, medications, and other factors.
How to Use the BAC Calculator
- 1
Enter your weight and select your biological sex.
- 2
Input the number of standard drinks consumed.
- 3
Enter the number of hours since you started drinking.
- 4
Click Calculate to see your estimated BAC.
- 5
Note: this is an estimate — never drive based on a calculator result.
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