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BACtrack Keychain Breathalyzer Portable Keyring Breath Alcohol Tester, Black

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List Price: $39.99
Price: $29.95 & FREE Shipping on orders over $35. Details
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  • Smallest BACtrack Breathalyzer ever made; Small enough to fit inside a purse or pocket and can be used as a keychain
  • Displays BAC results in easy-to-read 2 digit LED display
  • Innovative folding mouthpiece; Maximizes portability and ease of use; Three optional mouthpieces also included for multiple users
  • Wide test range - results displayed from 0.00 - 0.40 %BAC
  • FDA Cleared for personal use
21 new from $28.90 1 open box from $28.45

Frequently Bought Together

BACtrack Keychain Breathalyzer Portable Keyring Breath Alcohol Tester, Black + BACtrack Breathalyzer Mouthpieces Reusable Breath Alcohol Tester Mouth Piece Covers, Pack of 10
Price for both: $37.06

Buy the selected items together

Important Information

Legal Disclaimer
Actual product packaging and materials may contain more and different information than what is shown on our website. We recommend that you do not rely solely on the information presented and that you always read labels, warnings, and directions before using or consuming a product. Please see our full disclaimer below.

Product Description

Color: Black

The BACtrack Keychain Breathalyzer is a revolutionary portable breathalyzer that takes size and portability to the next level. The BACtrack Keychain Breathalyzer is a fully functional breath alcohol tester with an internal alcohol sensor, folding breath tube, and even optional mouthpieces. You can quickly and easily estimate your BAC, Blood Alcohol Content, by blowing through the mouthpiece for 5 seconds. Never before has a breathalyzer had accurate alcohol sensing technology in a design this small and affordable. You can take the product everywhere and test yourself, friends, family, or anyone who is curious about their Blood Alcohol Content. The innovative folding mouthpiece pulls out during testing and slides back down during storage – it’s that easy! Everyone will want to test themselves whether you’re at a party, bar, restaurant, or anywhere else alcohol is consumed. Learn how drinking alcohol affects your Blood Alcohol Content and always make smart, informed decisions. And you can trust the BACtrack Keychain Breathalyzer because of BACtrack’s history and experience with personal and professional alcohol breathalyzers.

From the Manufacturer

BACtrack Keychain Breathalyzer

Available in: Purple, Green, Blue & Black

The Leader in Breathalyzers

BACtrack, the most-trusted brand of breathalyzers, with over 13 years of experience in the industry, provides the most accurate, convenient and affordable breath alcohol testing devices on the market.

With its personal, professional and smartphone breathalyzers being sold in more than 20,000 retail stores in North America and in over 25 countries worldwide, BACtrack truly is the leader in breathalyzers.

BACtrack Keychain Breathalyzer

Perfect for BAC testing on the go!

Quickly and easily estimate your blood alcohol content with the small and affordable BACtrack Keychain Breathalyzer. The folding mouthpiece pulls out during testing and slides back down during storage – blow for accurate BAC results in just 5-seconds! Best of all, you can’t forget your Keychain Breathalyzer as it travels with you wherever you carry your keys.

  • Ultra-portable, take anywhere design
  • Easy to read, two-digit LED display
  • Accurate, reliable results from 0.00-0.40% BAC
  • Operates with one AAA battery, included
  • FDA 510(k) cleared for personal use
  • Full one-year warranty

BACtrack Keychain Breathalyzer Features

The Smallest Breathalyzer Ever Created

Measuring just 1.5 inch x 2.5 inch x 0.5 inch and weighing a mere 2oz., the BACtrack Keychain Breathalyzer is the smallest, lightest breathalyzer in the world. Its ultra-compact size makes it easy to carry in a purse or pocket and can even be used as a keychain.

Reliable, Accurate BAC Results

Powered by Advanced MicroCheck Sensor technology, the BACtrack Keychain Breathalyzer delivers reliable, accurate BAC results you can trust. You can expect up to 75 tests per single AAA battery.

Share With Friends and Family

With its innovative folding mouthpiece design and three included reusable mouthpieces, the BACtrack Keychain Breathalyzer is perfect for testing yourself as well as your friends and family. Gain peace of mind and keep your loved ones safe with BACtrack.

BACtrack Mobile Smartphone Breathalyzer BACtrack Vio Smartphone Keychain Breathalyzer BACtrack S80 Professional Breathalyzer BACtrack Element Professional Breathalyzer BACtrack S35 Personal Breathalyzer BACtrack Keychain Breathalyzer
Ideal Use Personal & Professional Personal Personal & Professional Personal & Professional Personal Personal
Accuracy Rating 10 - Most Accurate 7 - Very Accurate 10 - Most Accurate 9 - Extremely Accurate 7 - Very Accurate 6 - Accurate
LCD Screen
Bluetooth Connectivity
ZeroLine - Estimates time to 0.000% BAC
Battery Type Mini-USB Rechargeable Lithium Ion 1 x AAA battery 2 x AA batteries 2 x AAA batteries 2 x AAA batteries 1 x AAA battery
One Year Warranty

Product Details

Color: Black
  • Product Dimensions: 1.4 x 0.6 x 2.4 inches ; 2.1 ounces
  • Shipping Weight: 2.9 ounces (View shipping rates and policies)
  • Shipping: This item is also available for shipping to select countries outside the U.S.
  • Origin: China
  • ASIN: B006536ZXC
  • UPC: 088020572011 053786356632 850167002634 580098565419 069060197792 030955348186 031113253908 070321928505 097914414504 700621479031 044111636635 044113369555 069060190106
  • Item model number: BT-KC10
  • Batteries 1 AAA batteries required. (included)
  • Average Customer Review: 3.7 out of 5 stars  See all reviews (470 customer reviews)
  • Amazon Best Sellers Rank: #1,925 in Health & Personal Care (See Top 100 in Health & Personal Care)
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Customer Reviews

Easy to use and seems to work accurately.
Victor Davila
We wait until we're well below legal limit by using this - regardless if I feel like driving or not!
Rob Underwood
When you blow into it, you get different readings each time and number goes up and down.
Pen Name

Most Helpful Customer Reviews

297 of 312 people found the following review helpful By Matias on July 25, 2013
Color Name: Black Verified Purchase
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:


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.
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222 of 244 people found the following review helpful By Rob on March 31, 2012
Color Name: Black Verified Purchase
This thing is quite a battery hog (AAA size). Had an alocohol sensor unit that cost more and seemed to be more accurate than this one for a decade before it quit working. This one registered a 0.01 after a beer a few nights back- seems to work so far. Don't drink that much nowadays but I want to know just where I stand... One can get into serious trouble if he hurts/kills someone while driving impaired.

Will update this after I compare it to the BACtrack S80 fuel cell model that I recently ordered arrives.

Update: Drank two beers 24 oz. total. Here are the results as my body eliminated the alcohol. Three digit numbers on the left are the pricy fuel cell model results.

6:56pm .029 vs. .06 BAC
7:12pm .022 vs. .04
7:21pm .020 vs. .03
7:38pm .016 vs. .03
8:36pm .000 vs. .00

The two digit numbers on the right are this inexpensive keychain model. The three digit numbers on the left are the BACtrack S80 $136. model. My stomach was completely empty when I did the above comparison. My old alcohol sensor unit seemed to be more accurate than this one. A fuel cell model is the way to go if you really need accuracy and not a vague idea... This is little more than a keychain trinket/party toy as far as I am concerned.

Blew into a fuel cell looking model years back when a cop thought I was drunk. He was puzzled for I was well below 0.08 but had alocohol on my breath... Am glad I have an accurate fuel cell breathlizer now. Cheap insurance considering the potential ramifications of being over 0.08% BAC. Figure on the high probability of a blood test for any and all drugs if you look/smell/act impaired. The courts have upheld the use of blood tests at the discretion of the cops.

Went partying yesterday afternoon.
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69 of 80 people found the following review helpful By Colin A Bloch on May 13, 2013
Color Name: Black
I bought this at the same time as another unit which was nearly twice the price in order to have multiple data sources in order to make an informed decision about my (lack of) sobriety.

When used correctly, it registers consistently exactly 0.01 below my other unit. I don't know which is "correct", but with mathematical computations based on my body weight vs. number of fluid ounces of alchohol, both register either exactly or very close to what they are supposed to. When I say "correctly", I mean not within 15 minutes of having a drink, or no repeated blows too close together (as the directions clearly state and clearly what multiple reviewers chose to ignore.)

I had one isolated incident where it read 0.00 a couple of consecutive times, but setting it down for 10 minutes and trying again seemed to correct it's minor brain lapse.

The real negative here is that the battery is seemingly only good for a few days (with our use, maybe 10-12 blows.) I would love for other users (or the manufacturer) to chime in and let me know if this is a defective unit, or truly a design deficiency, because this would be a 5-star product without this issue. Regrettably with it, it's only 3.


After publishing this review, I mailed bactrack customer service. They responded within about 4 business hours of my request with this very nice reply - upping my rating to 4 stars, and will change to 5 if the new one gets the proper battery life:


Thank you for contacting us with your Customer Support issue. I'm sorry to hear that you are having a little trouble with your breathalyzer.

According to manufacturer specifications and general customer experience, the KC10 typically has a battery life of about 50-75 uses.
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Most Recent Customer Reviews

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