How Much is Too Much to Drink Before Driving? Check out These Blood Alcohol Content Charts to Find Out

Here are two sex-weighted charts as a method of calculating an approximate BAC level…

ALCOHOL IMPAIRMENT CHART
FEMALES

APPROXIMATE BLOOD ALCOHOL PERCENTAGE
Drinks
*
BODY WEIGHT IN POUNDS
EFFECT ON PERSON
90 100 120 140 160 180 200 220 240
0
.00 .00 .00 .00 .00 .00 .00 .00 .00
ONLY SAFE DRIVING LIMIT
1
.05 .05 .04 .03 .03 .03 .02 .02 .02
IMPAIRMENT BEGINS.
2
.10 .09 .08 .07 .06 .05 .05 .04 .04
DRIVING SKILLS SIGNIFICANTLY AFFECTED.
3
.15 .14 .11 .11 .09 .08 .07 .06 .06
4
.20 .18 .15 .13 .11 .10 .09 .08 .08
LEGALLY INTOXICATED.CRIMINAL PENALTIES IN ALLSTATES
** 

5
.25 .23 .19 .16 .14 .13 .11 .10 .09
6
.30 .27 .23 .19 .17 .15 .14 .12 .11
7
.35 .32 .27 .23 .20 .18 .16 .14 .13
8
.40 .36 .30 .26 .23 .20 .18 .17 .15
9
.45 .41 .34 .29 .26 .23 .20 .19 .17
10
.51 .45 .38 .32 .28 .25 .23 .21 .19

Subtract .01% for each 40 minutes of drinking.
* One drink is equal to 1¼ oz. of 80-proof liquor, 12 oz. of beer, or 4 oz. of table wine.
ALCOHOL IMPAIRMENT CHART
MALES

APPROXIMATE BLOOD ALCOHOL PERCENTAGE
Drinks
*
BODY WEIGHT IN POUNDS
EFFECT ON PERSON
100 120 140 160 180 200 220 240
0
.00 .00 .00 .00 .00 .00 .00 .00
ONLY SAFE DRIVING LIMIT
1
.04 .03 .03 .02 .02 .02 .02 .02
IMPAIRMENT BEGINS.
2
.08 .06 .05 .05 .04 .04 .03 .03
3
.11 .09 .08 .07 .06 .06 .05 .05
DRIVING SKILLS SIGNIFICANTLY AFFECTED.
4
.15 .12 .11 .09 .08 .08 .07 .06
5
.19 .16 .13 .12 .11 .09 .09 .08
LEGALLY INTOXICATED.

CRIMINAL PENALTIES IN ALL STATES
**
6
.23 .19 .16 .14 .13 .11 .10 .09
7
.26 .22 .19 .16 .15 .13 .12 .11
8
.30 .25 .21 .19 .17 .15 .14 .13
9
.34 .28 .24 .21 .19 .17 .15 .14
10
.38 .31 .27 .23 .21 .19 .17 .16

Subtract .01% for each 40 minutes of drinking.
* One drink is equal to 1¼ oz. of 80-proof liquor, 12 oz. of beer, or 4 oz. of table wine.