BACtrack Keychain Breathalyzer | Portable BAC Alcohol Tester | Black | 3 Mouthpieces Included | For Home & Personal Use

This is an update to my original review from over five years ago. My unit lasted for over 5.5 years before it would display only '0.0' during a test. Everything else worked so I assume the sensor finally wore out and/or it needed a factory calibration. (Note: BACtrack recommends periodic factory calibrations, but at $19.99/each it's simply not worth it for a $25 unit.) The BACtrack Keychain was definitely a cost-effective, reasonably-accurate solution for me at the time. But in the interest of greater accuracy and lifecycle costs, I decided to replace it with a more expensive, more accurate self-calibrating unit with a user-replaceable sensor. That said, I still give it a five star rating based on my overall five year experience. I first saw this device in a comparison test of breathalyzers in the April 2014 issue of 'Car and Driver' magazine. It tested as well as - in some cases better than - a unit costing 5x more. The device feels well-made for the price - not especially rugged but not cheap either. It operated as-described. It comes with a Duracell AAA battery as pictured. The instruction manual is clearly written and the table describing effects of increasing levels of alcohol was informative. I have no way of verifying the unit's accuracy but it seems to work properly, displaying roughly proportionate increases in BAC when consuming alcohol. After 15 hours with no alcohol it registered a BAC of 0.00. After one shot and a fifteen minute wait it indicated 0.03. After an additional 3/4 bottle of beer and fifteen minute wait I tested at 0.04. In the FAQs, when queried where the unit was made, BACTRack customer service responded, "We do all our design, testing, calibration and quality assurance here in California" but for whatever reason omitted that it is also "Assembled in China" as printed on the packaging. Overall I recommend this device: it feel adequately constructed for the price, seems to work as advertised. I can see it being fun at parties and could save your license!

The BACTrack is a great product for what it is- a small device that gives you an idea, or perhaps a means to gauge your level of intoxication. I find that it's best case usage scenario is to follow the instructions to the letter - i.e. don't eat/drink, consume alcohol, or smoke for 20 minutes or more before testing yourself. Wait an additional 20 minutes and test again. The second test is to determine if alcohol is still metabolizing in your body, due to the way it is absorbed by the body. Using the BACTrack in this manner allows me to gauge whether my blood-alcohol-concentration is rising or falling. As far as accuracy goes, it's no fuel cell-based breathalyzer employed by law enforcement, but it also wasn't $150 or more and doesn't require weekly calibration. Sensors and technology have come a long way in the last 20 years and there has been a market for these types of devices. I seem to recall multiple DUI offenders having breathalyzers installed in their vehicles as part of their sentence, in which a sensor similar to the one in this BACTrack would gauge their BAC and allow/deny operation of the vehicle. While the BACTrack explicitly says the device cannot be used as evidence in court, I believe what the device is really great for is to serve as a reminder of one's civil etiquette. Your responsibility to operate a motor vehicle safely, and discourage you from getting behind the wheel of your tank because now you're aware that you're a bit plowed. This is my second BACTrack and it works just as well as the previous one I owned, which was stolen by a friend during a long day of inebriation. He still uses it and hasn't had to calibrate it yet. I'm curious to have mine calibrated, but the instructions state it only needs to be calibrated every 6 months with light use. Perhaps I need to step up my game..

The Keychain Breathalyzer is really a great value, but like any measuring device, you HAVE to understand a little science and how to properly use it. When I first got this little doodad, I put the battery in and went hog playing around with it, drinking with some buddies. The next day, it started acting really funny. It would turn on and start counting down, and then shut off almost immediately. If I left it alone for several hours, I could do a test, but then it was unable to do another test. Sometimes I could do a test and it gave me the 'Lo' message. I thought the battery was dead. I checked the battery with a volt meter, and the battery didn't look dead at all. I thought I got a lemon... and then I got a new battery. Now it's fine. To those who have seen the "it was working great the first night, and then it quit on me" reviews, this is what's going on: RELIABILITY: This device seems power hungry, and I have a feeling that the AAA battery can't immediately produce the power it needs, so it needs to harvest the energy slowly while not in use so that it can do a test. I didn't like that this behavior isn't explicitly explained in the manual. The manual does say to wait a few minutes between tests. If you don't follow this, it will actually kill the battery. If you played with it non-stop all night and it won't work anymore on a seemingly good battery, replace the battery and use it properly. It will function perfectly. This is something that should be clearly addressed in the manual, and I think would eliminate the negative reviews that I have seen. Realize, this device was designed for a responsible drinker who wants to stay safe. That person will use it perhaps 4 times at most throughout an evening. ACCURACY: I've never been able to measure and track the phenomenon of BAC, so I had no idea what to expect. I looked at a table of BAC's, drink units, and body weight/height to see what a standard drink should do to me. I did a proper test, where I had 1 drink unit (1 12oz can of beer in this case) and waited 20min to do a test. It matched the table perfectly. And it's very consistent. If I repeat a test, it is always within 0.01 of the last. You don't necessarily have to wait the full 20 minutes, but there are caveats. If you are still absorbing alcohol in your GI tract, yet have absorbed all of it in your mouth and throat (you ate a big meal before drinking), the reading will be low because you haven't absorbed everything into your system yet (it will continue to rise even if you don't have another drink). If you're still absorbing alcohol in your mouth (ie. after a sip of hard liquor), it will read high because the alcohol takes longer to absorb through your mouth and throat. You can rinse your mouth and do a test to get a ROUGH idea anytime, but if you want to be sure about your reading, wait 20 minutes. If 20 minutes isn't possible and it's important, your environment isn't healthy. CALIBRATION: The official website says that it should be sent for calibration after 6mo - 1yr. Closer reading of the manual confirms what many professionals in the BAC field will say: Every Month. The manual states that under 'average' use, it will need to be calibrated after 6mo - 1yr. But under daily use, it may need calibration as often as once a month. I will periodically see what it reads my BAC 20 min after 1 standard drink, and send it off when it looks inconsistent or off. CONCLUSION: BAC was a much simpler concept in my head until I started reading and got this doodad. You have to learn a little science to understand what is going on. But it will help you understand that "feeling OK" is often not good enough. Really, this tool is most useful if you understand how alcohol interacts with your body. Breathalyzers are not a surefire or definitive way to measure 'drunkenness' because they are an indirect measurement that can be affected by many factors. However, if you would like a tool to give you a rough idea of what you can handle, and have the knowledge to understand what factors are at play, it's a damned educational gadget that I would recommend to anyone interested in some learnin'. At $30, it's a great deal. If you need more accuracy, or whatever, spend the money for a fuel-cell breathalyzer and get it calibrated every month. The BACtrack keychain is a good "back of the envelope" tool that can be very educational.

Got this thing about a year ago. It was fun to blow on and maybe know where you’re at. At best it’s in the ballpark of not even close to being right. Lost it for 3 months and now it doesn’t work The battery never exploded or anything the keychain just quit out. Save your money

Bought this because I now have a teenager. Period. This thing is great if you're trying to determine if someone's been drinking and if so to what extent. Had a blast playing around with it during and after a recent football game at the house. It does exactly that. It'll register .00 if you're not drinking and if you have, a number will come up that's generally pretty consistent with what people had been drinking during the game. It comes with a baggy of several disposable mouthpieces too. This may not be perfectly exact like some of the much more expensive options that are available out there, but it'll tell you if someone's been drinking and approximately how drunk they are. There's no way to calibrate and/or test the device to get an exact measurement on how precise it is, as far as I can tell, but that's not what we needed. It's perfect for our purposes. I'd say if you're in a situation or a profession where you need the ability to calibrate and get exact reads on an individual's alcohol consumption, definitely go with one of the higher end, higher priced models that are out there. Thanks for reading. Hope this helps!!

So I liked the idea of a keychain breathalyzer, but its not as convenient or accurate as advertised. I do not drive past 0.06 and this is not at all suitable for someone who wants to pace themselves and would be dangerous for those who drive just under the legal limit. The variance between measurements is easily +/- 0.02. You can read 0.08 15 minutes after one beer and it will fall to 0.00 after 30 minutes. Use of mouthwash takes 30 minutes to go from 0.11 to 0. As you can see, the suggested 15 minute interval in manual is insufficient for a completely accurate reading. I am not sure if my expectations were too high for the product, but it is better than nothing, but there are superior products on the market. In practice, it is functional but you have to not eat/drink for 1 hour, take at least 2 measurements 10-15 minutes apart and the average of this is somewhat reliable. A typical reading series without food or drink waiting 5 minutes may look like; 0.08 ,0.06,0.10, 0.08,0.08,0.06,0.08,0.06 so I would infer this would be 0.075 but the 95% CI would be 0.06-0.092. Its fun having a cheap product that correlates with BAX, but if your intention is to keep yourself out of trouble while driving close to the limit you should probably invest a bit more unless you enjoy doing drunk statistics. If you have this good of a memory on your nights out, you could probably just get the same estimate from writing down your servings and using an online calculator with body weight. Unfortunately people who drink more than one type of beverage will usually not know the alcohol content or remember how many, so this fills that gap, but I would advise spending a few more bucks for the better one. I've also seen false positives. After testing, I accidentally pressed the button without blowing on it and received a rating of 0.02, suggesting the device does not check if you are using it appropriately and assumes you are. Update: Died about a year later so I decided to go with another brand. Its nice for the money, but wouldnt recommend. The accuracy was never good without averaging, but the dealbreaker is really the low product life. I had assumed that semiconductor would be more durable but less accurate, but its really not great on durability aspect either.

It's not the best product for your money, from what I've read of other breathalyzers. However it will definitely tell you within a reasonable margin of error if you have been drinking. I haven't personally drank alcohol since I bought this a few months ago, but I have used it on another person who had been drinking, and they blew a .15, which was probably accurate, or at the very least it was accurate enough. If you blow anywhere over .08 you should not be driving, whether or not this thing is as accurate as a blood test. I do vaporize nicotine liquid, and if there happens to be any amount of alcohol in the liquid, I will get a false positive up to as high as .10 some times. This is the most important thing I want people to take away from this review. I think that goes to show how effective the product is. I am glad I waited several months to rate this product, because at first I wasn't even aware that there was alcohol in some of the liquids I was using in my cigarette pen, and since I started making my own liquid, I can make sure it is not in there. Some of the flavors I was buying were irritating my throat and I couldn't figure out why. Now I am pretty sure it was from the type of alcohol that was in some of the flavorings. If it weren't for trying this device over the past few months as I did, I would have considered it defective. The most important thing I want to convey is; if you use an electronic cigarette, you will get a false positive if you have been using nicotine liquid recently, and that false positive will last for quite some time. I tested myself after smoking some liquid with alcohol in it up to an hour later and was still getting a false positive.

I bought this for my wife to keep in her purse. She occasionally goes out with her friends and has a few drinks. She never drives if she is intoxicated but you can never be too safe to avoid both a potential accident or being pulled over and getting a DUI. We didn't buy this thinking it would be the most accurate breathalyzer on the market. I bought it because the price point was right, its pretty reliable and it's small enough to fit in her purse. You can never be too safe when it comes to having a drink and getting in your car. Now after having a few drinks and waiting a few hours, my wife has the piece of mind that she is able to legally drive and if she were to be pulled over she wouldn't be over or close to the legal limit. Additionally, it makes sure she is in the right state to drive. Pros: Inexpensive (especially compared to DWI costs) Small, fits in purse Has worked well every it has been used Seems to be relatively accurate for an inexpensive keychain breathalyzer Cons: This may have issues when it gets really cold since it is battery powered. It is not as accurate as the one's the police use, but you'd need to spend many times more to get that.