A personal breathalyzer is a small tester you own yourself and use to check your own breath after drinking, at home, at a party or before you decide how to get back. The devices in this category look alike on a store shelf, yet they differ in the sensor inside, in whether the maker publishes an accuracy figure and in how the unit is recalibrated once it ages. Below we compare them using only the makers' published specifications.
BACtrack S80 Pro, because it pairs a fuel cell sensor with a published tolerance and a battery set that lasts for a long run of tests.
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BACtrack C8, because its fuel cell sensor fits in a small pocket unit that can log results on your phone or work on its own.
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BACtrack Go, because it costs the least of the group and rides on a keychain, as long as you accept a semiconductor sensor and frequent recalibration.
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| Model | Sensor | Stated accuracy | Calibration | Best for |
|---|---|---|---|---|
| BACtrack S80 Pro | Fuel cell | +/- 0.005 at 0.100% BAC | Send-in service, annual check advised | Frequent personal use |
| BACtrack Trace Professional | Fuel cell | +/- 0.005 at 0.050% BAC | Send-in service, annual check advised | Precision in a slim body |
| BACtrack Mobile | Fuel cell with breath pump | +/- 0.005 at 0.050% BAC | Send-in, every 6 to 12 months | App logging without a screen |
| BACtrack C8 | Fuel cell | Not published by the maker | Send-in service, interval not published | Pocket use with optional app |
| BACtrack C6 | Fuel cell | Not published by the maker | Send-in service, interval not published | Keychain carry with an app |
| BACtrack Go | Semiconductor | Not published by the maker | Send-in, every 6 to 12 months | Rare, rough checks |
Figures are the maker's published specifications.
Who it suits: someone who tests often, wants a figure for tolerance printed by the maker and prefers a plain handheld over a phone app.
What to know: it is the bulkiest unit here at 4.8 oz with batteries, and the maker's two pages list different dimensions. Calibration means mailing it to the maker, so plan for a stretch without it. The maker states it meets DOT and NHTSA requirements for a personal screening device, which is a screening claim, not evidence grade.
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Who it suits: a person who wants a fuel cell sensor in something light, around 2 oz, and likes seeing past results in an app without being forced to use one.
What to know: the maker gives no numeric tolerance, so you cannot compare it head to head with the S80 or Trace on paper. The maker lists the C8 on its send-in calibration service but publishes no model specific interval. Our BACtrack C8 review covers the app side in more depth.
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Who it suits: someone who drinks rarely and wants a light, low cost reminder on a keychain, knowing it is a rough indicator rather than a precise reading.
What to know: semiconductor sensors react to more than ethanol and drift faster, which is why the calibration schedule is so tight. The manual itself says not to use the result to decide whether to drive. See our comparison of fuel cell vs semiconductor breathalyzer sensors before choosing this tier.
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Who it suits: a buyer who wants the published precision of a Pro Grade unit in a flatter body, about 3 oz, that slides into a jacket pocket.
What to know: the battery type differs between maker pages, so check the box before buying spares. There is no app. Read our BACtrack Trace Professional review for the full spec sheet.
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Start with the sensor. A fuel cell responds specifically to alcohol and holds its calibration longer, while a semiconductor sensor is cheaper but less stable and more easily confused by other substances. If you plan to test more than a handful of times a year, the fuel cell tier is the sensible floor.
Next, look for a published accuracy figure. A tolerance stated at a specific BAC level, such as plus or minus 0.005, tells you what the maker is prepared to stand behind.
Then check the calibration path. Most personal units go back to the maker by mail, which costs a fee and some days without the tester. Our guide on calibrating a breathalyzer explains the methods in detail.
Finally, think about where the tester will live. A keychain unit is always with you but runs on a small battery. A handheld with AA cells lasts much longer between battery changes. A phone linked model adds logs and time estimates but depends on your phone and an app.
If you are unsure which tier fits you, the breathalyzer finder asks four short questions and narrows the list, and our best breathalyzer ranking compares every category in one place.
A well maintained fuel cell unit used after the proper wait gives a useful estimate, but it remains a screening device and drifts until it is recalibrated.
Choose a fuel cell sensor if you test regularly, and consider semiconductor only for rare, rough checks where a low purchase cost matters most.
Follow the maker, which for the models here ranges from every six to twelve months for the Go and Mobile to an annual check advised for Pro Grade units.
No, these are personal screening devices and their results are not evidence, and the Go manual states that directly.
No, it only estimates the alcohol in your breath, so if you have been drinking the safe choice is not to drive at all.
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