How We Evaluate Scan Tools
Exactly how ScanToolAdvisor researches, compares and ranks OBD2 scanners – our sources, the nine points we compare, how we test, and what we don't do.
Plenty of “best scanner” lists claim every tool was “tested and ranked”. This page explains exactly how our reviews are made, including what we haven’t done yet, so you can decide how much weight to give them.
Who does the work
ScanToolAdvisor is run by Scott, a lifelong car enthusiast and a software engineer with 18 years of experience and a master’s degree in data science. He isn’t an ASE-certified mechanic, and the site doesn’t pretend otherwise. What it brings instead is careful, organised research: the same facts collected for every tool, every source written down, and gaps marked as gaps.
Where the facts come from
For each scanner we collect, in this order of trust:
- The manufacturer’s own pages – specs, vehicle coverage, update policy, subscription prices.
- Retailer listings – current pricing, bundle contents, which version is actually being sold.
- Published hands-on reviews and owner feedback – how the tool behaves in real use, and where the marketing overpromises.
Every source is recorded with the date it was checked. When sources disagree – a manufacturer says “free lifetime updates” but an older review reports a renewal fee – we say so on the page and keep digging rather than picking the convenient answer.
The nine points we compare
Every scanner is described the same way, so you can compare them side by side:
| Point | What we record |
|---|---|
| Price | A typical price band (e.g. $100–$200), since store prices change almost daily |
| Type | Bluetooth dongle, handheld or tablet |
| Connection | Cable, Bluetooth or Wi-Fi |
| Systems covered | Engine only, engine + ABS, engine + ABS + airbags, or every system |
| Active tests | Whether it can command parts on and off (bidirectional) |
| Live data | How much real-time sensor data it shows, and whether it can graph it |
| Updates | Free for life, free for a while then paid, or paid features |
| App quality | For phone-based tools, how clear and reliable the app is |
| Best for | Beginners, DIYers or pros |
How we rank
Rankings are a judgment of value for the person each tool suits, not a single score:
- A tool must do its core job well for its intended user before anything else counts.
- Ongoing costs matter as much as the sticker price – see Scanner Subscriptions and Update Fees.
- Plain-English explanations and good coverage for common US cars count for more than long feature lists.
- Badges like “Best Overall” go to the tool we’d recommend first to most people in that group.
Hands-on testing
Our current reviews are research-based. As tools are tested in person, each review will say so clearly and add our own photos. Every tested tool goes through the same checklist on the same cars:
| Test | What we check |
|---|---|
| Setup | Unboxing to first scan: pairing, accounts, updates needed |
| Vehicle ID | Does it read the VIN and identify the car correctly? |
| Read and clear codes | Engine codes, then ABS and airbag codes where supported |
| Live data | Speed, readability, graphing and recording |
| Active tests and resets | Where supported: does each one we try actually work? |
| Connection | Cable length or wireless range and stability |
| Updates and cost | What’s free, what needs a subscription, and what happens if you stop paying |
Data analysis
The Trends page goes beyond product specs, using public data such as NHTSA’s database of owner complaints. Each analysis is a Jupyter notebook that downloads the data, works out the numbers and saves them for the page, so every figure can be traced back to its source and re-run when new data comes out.
What we don’t do
- No paid placements. No brand can pay for a ranking, a badge or a better review.
- No fake testing claims. If we haven’t used a tool, the review doesn’t say we did.
- No invented reviews or ratings. Owner comments only appear with the owner’s permission.
- If a manufacturer ever lends or gives us a tool to test, the review will say so.
How the site makes money
Today the “Check Price” buttons are plain links and earn nothing. In the future we plan to earn a small commission through the Amazon Associates program; when that starts, the About page and the footer will say so, and it will never change the rankings.
Corrections
Prices, update policies and features change. If something here is out of date or wrong – especially if you make one of these tools – please contact us. Corrections are made promptly and the page’s date is updated.