BAC calculator
BAC calculator: what your breath or blood reading can mean
You were stopped and tested, and now one number could cost you your license.
A professional answers 24/7 and reviews your breath or blood reading with you for free.
Your drinks and hours
Your estimate
Example: 4 drinks, 2 hours, 180 pounds
.071BAC
A .071 result is under .08, yet you can still be charged, so have a DUI defense lawyer check the test.
Call for my free review (877) 317-9931 Between .05 and .08, NHTSA lists reduced coordination and difficulty steering. That is under the .08 limit everywhere but Utah. About 4 hours and 43 minutes until zero. Never use this estimate to decide whether to drive.What this number means
How long until zero
One standard drink is 12 ounces of beer at 5%, 5 ounces of wine at 12%, or 1.5 ounces of liquor at 40%. Each holds 14 grams of pure alcohol (CDC). A tall pour counts as more than one.
Alcohol leaves the body at about .015 per hour (BGSU). Water and coffee do not change that rate, so a morning drive after a late night can still test over the limit.
What each level means
| BAC | What NHTSA lists |
|---|---|
| .02 | Some loss of judgment; decline in visual functions |
| .05 | Reduced coordination; difficulty steering |
| .08 | Poor muscle coordination; harder to detect danger; about 4 times the crash risk |
| .10 | Reduced ability to keep lane position and brake |
| .15 | Far less muscle control; at least 12 times the crash risk |
The levels come from NHTSA's ABCs of BAC. The legal limit is .08 everywhere except Utah, where it is .05 (NHTSA). So if your test came back near .08, ask how the machine was checked and when the sample was taken. The tool uses the Widmark equation. It divides the grams of alcohol by your body weight in grams times a ratio, .68 for men and .55 for women, then multiplies by 100 (Indiana University). Then it takes off .015 for each hour.How the estimate is figured
If you were arrested
Call first. The license hearing clock is shorter than the court case, and a DUI lawyer files the request for you.
Most states give you 7 to 30 days. The DUI DMV hearing counter gives your last day.
Questions people ask
How many drinks to get to .08?
It depends on weight, sex and time. For a 180-pound man, a fifth drink in 2 hours can be the one that passes .08. A lighter person gets there sooner.
How long does it take for BAC to go down?
Only time lowers it. Coffee, water and sleep do not speed that up.
Is a BAC calculator accurate?
No calculator is exact. Food, medication, health and how fast you drank all change the real number. Use it to understand a reading you were given.
Can I use this result in court?
No. A calculator cannot stand in for the test the police ran. A DUI lawyer can tell you whether the breath or blood test in your case was done correctly.
What to do now
Your BAC calculator result cannot stand in for the test the police ran. Your license hearing clock is shorter than the court case, and it is counted in days. Call now so a DUI defense lawyer can file your hearing request before the deadline and ask for the police records.
Call for my free review (877) 317-9931
A professional answers 24/7 and reviews your breath or blood reading with you for free.
Send your case details
Send your state, your arrest date and the date on your license notice. Those dates set your deadline, so the call starts there.