What this calculator does
Every input on this bac calculator maps to a real decision, so the output is something you can act on immediately, not a rough ballpark you'll have to double-check elsewhere.
Estimates blood alcohol concentration — not a substitute for testing.
How to use the BAC Calculator
- Enter your values in the fields on the left.
- Results update automatically.
- Use the action buttons to copy, share or print.
The formula
BAC = (alcohol grams / (body water × r)) − 0.015 × hours
Worked example
3 drinks, 70 kg male over 2 hours ≈ 0.06%.
Common mistakes
- Under-counting drinks
- Ignoring food
- Assuming linear metabolism
When to use it
Use only for education. Never drive after drinking.
Pro tips for the BAC Calculator
- Copy the result to paste it directly into email, Notion, or a spreadsheet cell.
- Use Print / PDF to export a clean, ad-free summary you can share with a client or advisor.
- The chart updates live — drag values up and down to build intuition for how the formula behaves.
Frequently asked questions
›Legal limit?
US 0.08%, many countries 0.05%.
›Standard drink?
14g pure alcohol — 12 oz beer, 5 oz wine, 1.5 oz spirits.
›Metabolize rate?
~0.015 BAC/hour.
›Food effect?
Slows absorption, doesn't reduce total.
›Safe to drive?
Never — even below limit impairs.
›How accurate is this bac calculator?
The formulas match the standard textbook definition shown above. Rounding is applied only for display; underlying computation uses full floating-point precision. For regulated health & fitness decisions, always confirm with a qualified professional.
›Can I use this on mobile?
Yes — the bac calculator is fully responsive, and results, charts, and the share button all work on phones and tablets.
Embed this calculator
Drop the BAC Calculator into your own site or blog post. Free to use — a small “Powered by CalcPilot” link is appreciated.
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