血中アルコール濃度計算機
BAC値を推定
This calculator gives a rough estimate of blood alcohol concentration (BAC) based on the Widmark formula. It is intended for general information only and should never be used to decide whether it is safe to drive.
How it's calculated
The estimate uses the Widmark formula: BAC = (alcohol consumed in grams / (body weight × distribution ratio)) × 100, minus an elimination rate of about 0.015% per hour since drinking began.
Example
A 70 kg person who has had 3 standard drinks has an estimated BAC of roughly 0.06%, though individual factors can shift this considerably.
よくある質問
Is this an exact measurement?
No. The Widmark formula is an approximation. Actual BAC depends on many factors — food intake, medication, liver function, drink strength, and individual metabolism — that this calculator cannot account for.
Can I use this to decide if I’m safe to drive?
No. Never use an estimated BAC to decide whether to drive. Legal limits and actual impairment vary by individual and jurisdiction; the only safe choice after drinking is not to drive.
How long does it take to fully metabolize alcohol?
On average, the body eliminates alcohol at roughly 0.015% BAC per hour, but this varies by individual and cannot be meaningfully sped up.