About your Blood Alcohol Content (BAC)
Blood Alcohol Content or BAC measures the ratio of alcohol in the blood. BAC of 0.10 means one part alcohol for every 1000 part of blood. Note that 0.08 BAC is legal definition of intoxication in Idaho. To calculate your BAC
- Select the appropriate chart - males or females
- Select row with approximate weight [left column]
- Select number of drinks consumed [top row]
- Intersection of #2 and #3 is BAC if total number of drinks consumed within ONE HOUR
- If drinks were consumed over more than one hour use the Time Factor table – subtract the factor from your BAC as calculated in #4
For Males
Body weight (lbs) |
1 drink |
2 drinks |
3 drinks |
4 drinks |
5 drinks |
6 drinks |
7 drinks |
8 drinks |
9 drinks |
10 drinks |
100 |
.043 |
.087 |
.130 |
.174 |
.217 |
.261 |
.304 |
.348 |
.391 |
.435 |
125 |
.034 |
.069 |
.103 |
.139 |
.173 |
.209 |
.242 |
.278 |
.312 |
.346 |
150 |
.029 |
.058 |
.087 |
.116 |
.145 |
.174 |
.203 |
.232 |
.261 |
.290 |
175 |
.025 |
.050 |
.075 |
.100 |
.125 |
.150 |
.175 |
.200 |
.225 |
.250 |
200 |
.022 |
.043 |
.065 |
.087 |
.108 |
.130 |
.152 |
.174 |
.195 |
.217 |
225 |
.019 |
.039 |
.058 |
.078 |
.097 |
.117 |
.136 |
.156 |
.175 |
.198 |
250 |
.017 |
.035 |
.052 |
.070 |
.087 |
.105 |
.122 |
.139 |
.156 |
.173 | For Females
Body weight (lbs) |
1 drink |
2 drinks |
3 drinks |
4 drinks |
5 drinks |
6 drinks |
7 drinks |
8 drinks |
9 drinks |
10 drinks |
100 |
.050 |
.101 |
.152 |
.203 |
.253 |
.234 |
.355 |
.406 |
.456 |
.507 |
125 |
.040 |
.080 |
.120 |
.162 |
.202 |
.244 |
.282 |
.324 |
.364 |
.404 |
150 |
.034 |
.068 |
.101. |
135. |
169 |
.203 |
.237 |
.271 |
.304 |
.338 |
175 |
.029 |
.058 |
.087 |
.117 |
.146 |
.175 |
.204 |
.233 |
.262 |
.292 |
200 |
.026 |
.050 |
.078 |
.101 |
.126 |
.152 |
.177 |
.203 |
.227 |
.253 |
225 |
.022 |
.045 |
.068 |
.091 |
.113 |
.136 |
.159 |
.182 |
.207 |
.227 |
250 |
.020 |
.041 |
.061 |
.082 |
.010 |
.122 |
.142 |
.162 |
.182 |
.202 | The Time Factor
Hours since first drink |
Subtract this from BAC |
1 |
.015 |
2 |
.030 |
3 |
.045 |
4 |
.060 |
5 |
.075 |
6 |
.090 | Source: Evans, Glen and Robert O'Brien (1991) The Encyclopedia of Alcoholism. Note: Charts are to be used as general guidelines. Other factors such as person's reaction to alcohol, use of medication or emotional states are not considered here. Effects of blood alcohol content on thinking, feeling and behavior:
0.02 – Insignificant body warmth, mild sedation 0.07 – Judgment impaired, loss of inhibition 0.08 - Legal definition of intoxication in Idaho. Poor muscle co-ordination, inability to detect danger, increased mental and physical impairment. 0.15 – Major mental and physical impairment. 0.20 - No motor control 0.40 - Unconsciousness | 
