Alcohol Withdrawal Time

The Alcohol Withdrawal Time Calculator is a free tool that calculates the time it takes for alcohol to break down based on the amount of alcohol consumed, weight, and time when drinking ended. It can calculate the amount of pure alcohol, the time it takes to break down, the time when alcohol leaves the body, the estimated breath alcohol concentration, whether or not you can drive, and the progress of alcohol breakdown.

This tool provides estimated values based on general theoretical formulas and does not guarantee medical or legal judgments. Alcohol metabolism rates and breath alcohol concentrations vary significantly depending on individual factors such as constitution, age, gender, health status, medication, food intake, and drinking environment. Even if the estimated breath alcohol concentration is below the legal limit, it does not guarantee safety for driving or work. We assume no responsibility for any damages, accidents, or disadvantages resulting from the use of this tool. When driving or making important decisions, if you have any concerns whatsoever, please always undergo testing by professional institutions or refrain from driving/working.

How to Use

Enter your "weight" and "drinking end time".
Input the amount and type of alcoholic beverages consumed.
The following will be automatically displayed: "Pure alcohol amount", "Metabolism time", "Estimated sober time", "Estimated breath alcohol concentration", "Driving assessment", and "Metabolism progress".

What is Alcohol Metabolism Time?

The time for alcohol to leave your system (the time until it's completely metabolized) is determined by the following factors:

Basic Principles

Metabolism rate proportional to weight:
Alcohol is primarily metabolized in the liver. Generally, higher body weight leads to faster metabolism.
Pure alcohol amount (g) ÷ Metabolism rate (g/h) = Metabolism time (h)
Estimated metabolism rate: Body weight × 0.1 g/h (Example: 70kg → about 7g/h)

Estimated Metabolism Time by Case

Drinking Content	Alcohol Amount (g)	Metabolism Time for 70kg Person	Notes
350ml beer can (5%) ×1	~14g	~2 hours	Typical light drinking
500ml beer can (5%) ×2	~32g	~4.5 hours	Substantial drinking
120ml wine glass (12%) ×2	~23g	~3.3 hours	Common amount for women dining out
180ml sake (15%) ×2 go	~43g	~6 hours	Standard izakaya drinking
100ml shochu (25%) ×3	~60g	~8.5 hours	Heavy drinking
60ml whiskey (40%) ×3	~58g	~8.3 hours	Assumed as rocks or straight
Drinking party totaling 80g+	80g+	11+ hours	May remain until next morning

Important Considerations

Individual Differences

Lighter individuals take longer to metabolize the same amount
Women and elderly tend to have slightly lower metabolism capacity
Drinking on empty stomach accelerates absorption, causing rapid blood alcohol spike

Relationship with Breath Alcohol Concentration (mg/L)

Blood Alcohol Concentration (BAC) above 0.15mg/L is considered driving under influence
It's important not just to be completely sober, but to drop below safe driving levels

Practical Guidelines

Situation	Safety Line
2×500ml beers at 10pm	Metabolized by ~6am next morning
3 whiskeys at midnight	~9-10am next day
Need to drive at 7am	Ideal to finish drinking by 9pm previous day

Supplement: Coordination with Alcohol Calculator

By accurately entering "drinking amount", "drinking end time", and "weight" in the tool, you can:

Estimated sober time
Current metabolism progress
Estimated breath alcohol concentration

All in real-time.

If needed, we can also provide detailed explanations about "countermeasures for different work/driving scenarios" and "drinking patterns that prolong intoxication". Please let us know if you'd like this information.

Notes

This tool is available for free.

*This program was created and tested using PHP8.2.22.
*Please send us your opinions and requests (requests for improvements) for all users.