BAC Chart by Weight and Number of Drinks

Estimate your blood alcohol content from how many standard drinks you've had within the last hour, by body weight and biological sex. Values use the Widmark formula with a 0.015% per-hour metabolism rate already subtracted.

Below 0.04%0.04% – 0.08%Above 0.08%

Male (r = 0.68)

Drinks	100 lb	120 lb	140 lb	160 lb	180 lb	200 lb	220 lb	240 lb
1	0.030	0.023	0.017	0.013	0.010	0.008	0.006	0.004
2	0.076	0.061	0.050	0.042	0.035	0.030	0.026	0.023
3	0.121	0.098	0.082	0.070	0.061	0.053	0.047	0.042
4	0.166	0.136	0.115	0.098	0.086	0.076	0.067	0.061
5	0.212	0.174	0.147	0.127	0.111	0.098	0.088	0.079
6	0.257	0.212	0.179	0.155	0.136	0.121	0.109	0.098
7	0.302	0.250	0.212	0.183	0.161	0.144	0.129	0.117
8	0.348	0.287	0.244	0.212	0.187	0.166	0.150	0.136

Female (r = 0.55)

Drinks	100 lb	120 lb	140 lb	160 lb	180 lb	200 lb	220 lb	240 lb
1	0.041	0.032	0.025	0.020	0.016	0.013	0.010	0.008
2	0.097	0.078	0.065	0.055	0.047	0.041	0.036	0.032
3	0.153	0.125	0.105	0.090	0.078	0.069	0.061	0.055
4	0.209	0.172	0.145	0.125	0.110	0.097	0.087	0.078
5	0.265	0.219	0.185	0.160	0.141	0.125	0.112	0.102
6	0.321	0.265	0.225	0.195	0.172	0.153	0.138	0.125
7	0.378	0.312	0.265	0.230	0.203	0.181	0.163	0.149
8	0.434	0.359	0.305	0.265	0.234	0.209	0.189	0.172

A “standard drink” equals 0.6 oz (14 g) of pure alcohol — roughly a 12 oz beer at 5% ABV, 5 oz of wine at 12%, or 1.5 oz of spirits at 40%. Values assume consumption over roughly one hour.

How to Read the BAC Chart

1
Pick the table matching your biological sex.
Men distribute alcohol across more body water, so at the same weight and drink count their BAC lands lower. Women typically reach a BAC about 20–30% higher.
2
Find the column closest to your body weight in pounds.
Round to the nearest 20-lb (~9 kg) increment. A 155 lb woman reads the 160 lb column.
3
Read across the row for your total standard drinks.
For each extra hour past the first one, subtract 0.015% from the cell value. Two hours in? Subtract 0.015%. Three hours in? Subtract 0.030%.

What Do These BAC Numbers Mean?

0.00 – 0.04%

Minimal to mild effects. Legal to drive in most countries.

0.04 – 0.08%

Noticeable buzz; impaired judgment and reaction time. Over the limit in many countries (AU, DE, FR).

0.08 – 0.15%

Illegal to drive in the US and most jurisdictions. Poor coordination, slurred speech, impaired perception.

0.15%+

Severe intoxication. Risk of blackout, alcohol poisoning, and injury rises sharply.

Want a More Precise Estimate?

The chart assumes standard drinks within one hour. Use the calculator for custom drink sizes, ABV, longer timelines, and country-specific legal limits.

Open the BAC Calculator