How we review breathalyzers from published specs

Our reviews are based on the manufacturer's published specifications and public documentation. For each model we collect the product page, the user manual, the calibration or service page, the warranty terms and any technical sheet the maker makes public. Where a maker publishes a regulatory listing or an approval, we note where it can be checked.

Retail listings, marketing claims without a source and forum posts do not count as evidence. If a seller writes "police grade" and the maker's own documents do not support it, the claim does not appear on our page.

When a detail is missing from the maker's documentation, we say "not published by the maker" instead of guessing. A missing accuracy statement is itself useful information, and we treat it that way.

We do not run lab tests

We do not test breathalyzers in a laboratory, we do not own calibrated reference equipment, and we never write as if we did. No page on this site presents a reading as our own result. A fair lab comparison needs certified reference standards and controlled conditions, which a review site cannot honestly claim.

What we can do well is read documentation carefully, compare like with like and explain the trade-offs. That is the job we set ourselves.

Two facts decide most of a personal tester's real value: the type of sensor and how calibration works.

A fuel cell sensor reacts specifically to alcohol and holds its readings better over time. A semiconductor sensor is cheaper but can respond to other substances and drifts faster. Professional fuel cell units sit a grade higher and are built for frequent use by employers and screening programs. The differences are explained in our fuel cell vs semiconductor breathalyzer comparison.

Every sensor needs calibration to stay accurate. We look at how often the maker asks for it, whether you send the unit back, swap a sensor module or have it done at a service point, and whether the maker publishes what that service involves. A tester that cannot be recalibrated is a short-term tool, however good it looks on day one. Our guide on calibrating a breathalyzer goes into the details.

The Spec score is our editorial summary of how well a model's published specifications fit its intended use. It is a transparent rubric, not a test result and not a rating from users. It is shown in words (strong, solid or basic for its category), never as stars or a mark out of ten.

The rubric looks at five criteria, listed from the greatest weight to the smallest:

• Sensor type. This carries the most weight. A fuel cell or professional fuel cell sensor scores higher than a semiconductor sensor, because the sensor sets the ceiling for everything else.
• Stated accuracy, published or not. The second largest weight. A model scores higher when the maker publishes an accuracy statement with the conditions it applies to, and lower when there is no figure or only a vague claim.
• Calibration method and access. A substantial weight. We favor documented calibration intervals, a clear service route and options such as replaceable sensor modules, and mark down units with no documented calibration path.
• Warm-up and usability. A smaller weight. Warm-up time, display clarity, blow detection, battery type and whether the unit is easy to use correctly all count here.
• Support and mouthpieces. The smallest weight. We look at warranty terms, the availability of replacement mouthpieces and how easy it is to reach the maker.

Each model is scored against others in the same category. A keychain tester is compared with other keychain testers, and a wall-mounted unit with other professional units, so a strong result in one category does not mean the same thing as in another.

What the Spec score cannot tell you

The rubric rewards good documentation and sound design choices. It cannot tell you how a specific unit behaves in your hands, how a sensor ages in a humid car, or whether a batch had a fault. That is why every review also lists the questions to ask before buying and the conditions that affect any reading, such as the breathalyzer test routine and the wait after the last drink.

We do not crown one best device for everyone. A parent checking a teen driver, a person who wants a pocket check before deciding to call a cab and a safety manager screening a crew need different things. Our best breathalyzer ranking and the category pages name a pick for each use case and explain in one line why it fits.

No maker or seller can pay for a review, a better position in a ranking or a mention in a guide. We do not accept free products in exchange for coverage, and nobody outside the editorial team sees a page before it goes live. If a maker writes to us, the only thing that can change a page is a documented correction to a specification.

The site is funded by the Amazon Associates program, and most model pages carry a "Check price on Amazon" button. We earn a commission if you buy through our links, at no extra cost to you.

• We link to the listing that matches the exact model we describe, sold or fulfilled in a way that makes returns and warranty straightforward where we can find one.
• We avoid listings that bundle a different model, an older sensor version or unclear accessories under the same name.
• If a model has no suitable Amazon listing, we show no button and link to the maker's page without a tag.
• Commission rates do not enter the Spec score or the order of any ranking.

The full statement is on our affiliate disclosure page.

Makers revise products, firmware and documents. We revisit pages when documentation changes and when readers report a mismatch. If you find a specification that differs from the maker's current documents, write to support@breathalyzer.io with the page, the model and a link to the source. We check every report and update the page when the source supports it.