The best OBD-II scanners in 2024

The best OBD-II scanners no longer expensive luxuries only your local mechanic can afford. These diagnostic machines are more affordable than ever, and they are a must-have tool for car owners — with the potential to save you a costly trip to the mechanic. The question is, which one do you choose?

There are a seemingly-infinite number of OBD-II scanners on sale right now, but they're not all made equally. Fortunately we've spent a great deal of time testing OBD-II scanners over the years, many of which cost less than $200, and know exactly what to look for — no matter what kind of car you have.

Here are our top picks for the best OBD-II scanners you can buy right now.

OBD-II/EOBD scanners work on almost all passenger vehicles sold in the United States since 1996, in Canada since 1998, in the European Union since 2004, and in Australia, Mexico and New Zealand since 2006. If you're unsure where an OBD-II scanner plugs in, gere's how to find your car's OBD-II port on North American cars. If you're living elsewhere, here's how to find your OBD-II/EOBD port worldwide.)

Not all the best OBD-II scanners are created equally, though. Generally speaking you'll come across two distinct types of devices: handhelds and wireless scanners. Those names are fairly self-explanatory, but there's a huge variance in what those scanners look like and the kinds of features they have to offer. 

In either case, however, there are there are several high-performance OBD-II scanners that cost less than $200. Long gone are the days where the best OBD-II scanners are unaffordable luxuries, and they are must have tools in every driver's arsenal.

The quick list

Here are the best OBD-II scanners you can buy right now, based on our own hands-on testing. You can scroll down the page to find more in-depth information about each mode, and what makes them so good at what they do.

What are the best OBD-II scanners?

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Best OBD-II scanner overall

Top Pick

(Image credit: Tom's Guide)
Helps make driveway mechanics feel like a true professional

Specifications

Display/size: Color/2.8 inches
Bluetooth/handheld: Yes/Yes
I/M Readiness test: Yes
Displays live data: Yes
Number of keys: 9
Warranty: 1 year
Size: 7.2 x 3.4 x 1.1 inches
Weight: 6.5 ounces

Reasons to buy

+
Compact and easy to carry
+
Resets battery test and oil lights
+
Handheld and app-based diagnosis
+
Offers repair instructions and parts needed

Reasons to avoid

-
Interface only uses text
-
Keys need a lot of pressure

The Innova 6100P is the kind of OBD-II scanner that will add a professional feel to any amateur mechanic job. That's certainly how we felt during our testing, anyway. This crossover device is able to operate as a standalone handheld unit, though its connection to the Innova app offers a great many more diagnostic abilities.

As we found during testing for our Innova 6100P review, this is a scanner that has a more involved set-up than most. But once connected we found that the scanner was easy to use, and managed to complete tasks very quickly

We feel that the $140 Innova 6100P has all the features any driver will need from an OBD-II scanner. Its 2.8-inch color screen displays everything from live data to fault codes to a pre-inspection I/M readiness check. It can even predict when components might fail in the near future, and what repairs and parts your car may need at any given time.

Read our full Innova 6100P review.

Best mobile OBD-II scanner

Innova CarScan Mobile 1000 in usebest value awards badge

(Image credit: Tom's Guide)
Innovative diagnostic features in a compact design

Specifications

Display/size: None
Bluetooth/handheld: Yes/No
I/M Readiness test: Yes
Displays live data: Yes
Number of keys: None
Warranty: 1 year
Size: 2.0x 1.5 x 1.0 inches
Weight: 0.9 ounces

Reasons to buy

+
Easy to set up
+
Small and compact
+
Excellent companion app
+
Can predict future problems and suggest repairs
+
Works as a standalone automotive gauge

Reasons to avoid

-
Relies on two separate apps
-
Both apps feature ads

The Innova CarScan Mobile 1000 is one of the most innovative Bluetooth OBD-II scanners we've ever tested. Not only is it the easiest wireless OBD-II module we've ever set up, it also packs in a lot of the same incredibly useful and innovative features you'd find on larger Innova scanners.

We found that the CarScan Mobile 1000 offered a huge range of diagnostic features, including Innova's predictive software that can identify potential problems before they go wrong. Better still it has the same part and repair suggestion features, so you know exactly what to ask your mechanic for. On top of that, if you want the scanner to turn your phone into a second set of automotive gauges, that is an option.

Read the full Innova CarScan Mobile 1000 review

Best cheap OBD-II scanner

Topdon ArtiDiag500 displaying diagnostic trouble code

(Image credit: Tom's Guide)
One of the best OBD-II scanners available for under $200

Specifications

Display/size: Color touchscreen/5-inch
Bluetooth/handheld: No/Yes
I/M Readiness test: Yes
Displays live data: Yes
Number of keys: 4
Warranty: 2 years
Size: 9.1 x 4.9 x 1.4 inches
Weight: 1.6 pounds

Reasons to buy

+
Large range of diagnostic tests
+
Wi-Fi and automatic updates
+
Strudy, rugged design

Reasons to avoid

-
Heavy and cumbersome design
-
Cable is shorter than we'd like

The Topdon ArtiDiag500 is another OBD scanner that blurs the line between professional and amateur use. While it looks more like a rugged gaming handheld than other OBD-II scanners, it's actually one of the most capable ODB-II scanners you can get as a consumer. It's able to monitor brakes, airbags, battery health, run an I/M pre-inspection test and also displaying live car data.

What we didn't like about the ArtiDiag500 was that the cable wasn't quite long enough to reach the engine bay and you'll need to disconnect it for storage. Still, we were big fans of the fact it runs on a version of Android and can automatically update its software. That, along with Wi-Fi and the rechargeable battery, are pretty rare features in our experience.

This may be a big and heavy OBD-II scanner, but at $170 it's also one of the best OBD-II scanners you can get for the price.

Read our full Topdon ArtiDiag500 review.

Best OBD-II scanner for older cars

(Image credit: Tom's Guide)
The ideal scanner if you have an older car

Specifications

Display/size: Color/3.5 inches
Bluetooth/handheld: No/Yes
I/M Readiness test: Yes
Displays live data: Yes
Number of keys: 8
Warranty: 1 year
Size: 6.8 x 2.6 x 1.0 inches
Weight: 10.5 ounces (1.4 pounds with 84-inch cable)

Reasons to buy

+
Includes cables compatible with pre-1996 vehicles
+
Offers repair advice and suggestions
+
Can reset your oil-change light

Reasons to avoid

-
Rather heavy for its size
-
Doesn't have a manual or quick-start guide

The Bosch OBD 1300 diagnostic scanner differentiates itself by offering cables that can connect with a range of pre-1996 cars — including those from Chrysler, Ford, GM, and Toyota. That's not to say you can't use it with newer cars. This scanner offering support for a wide range of diagnostic problems on cars from 1996 to 2013— and offers a database of over 26 million repair suggestions

The downside is that this scanner can't draw power from the OBD port. That means you'll have to plug it into your car's cigarette lighter or have some AA batteries handy. There's also no manual or quick start guide, so we had to download a copy from the Bosch website.

It's a little pricey too, but if you're the proud owner of an older car and still need an OBD-II scanner to check out what's going on under the hood, this is worth picking up.

Read our full Bosch OBD 1300 review.

Best rugged OBD-II scanner

(Image credit: Tom's Guide)
Like diagnosing your car with a Nintendo Switch

Specifications

Display/size: Color/4.3 inches
Bluetooth/handheld: No/Yes
I/M Readiness test: Yes
Displays live data: Yes
Number of keys: 7
Warranty: 1 year
Size: 7.8 x 3.8 x 1.2 inches
Weight: 1.1 pounds

Reasons to buy

+
Almost complete range of diagnostic testing
+
Soft-edged, rugged design
+
Comes with microSD card and hard case

Reasons to avoid

-
Lacks touchscreen
-
No option for battery power

Foxwell's NT614 Elite diagnostic scanner is impressive in how it's squeezed a large 4.3-inch display into such a small scanner. It doesn't have a touchscreen or a battery, but we found this rugged scanner to be powerful and capable or probing a great many car problems.

It should be no surprise that the Foxwell NT614, like the Topdon ArtiDiag500, is built for professionals and amateurs alike. It packs in the ability to graph data, cancel warning lights, as well as monitoring your battery charging system, airbags, brakes and transmission. Other useful features includes microSD storage, and programmable keys.

Read our full Foxwell NT614 Elite review.

Best dual-purpose OBD-II scanner

Best OBD-II scanners: Ancel BD310

Ancel BD310 (Image credit: Tom's Guide)
A handy OBD-II scanner than can perform double duty

Specifications

Display/size: Color/2 inches
Bluetooth/handheld: Yes/yes
I/M Readiness test: Yes
Displays live data: Yes
Number of keys: 4
Warranty: 3 years
Size: 5.1 x 2.4 x 0.6 inches
Weight: 5.4 ounces

Reasons to buy

+
Light and compact
+
Works as scanner and secondary car display
+
Offers handheld and Bluetooth scanning capabilities

Reasons to avoid

-
Interface is too minimalist
-
Screen is small

Ancel's BD310 is a dual-purpose scanner capable of operating as a standard handheld, and when connected to a smartphone via Bluetooth. Better still, it's capable of turning into a secondary display displaying various key engine details inside the cabin.

We found that the BD310 was one of the easiest scanners to keep around, because it's small and light enough to fit inside your glovebox. Granted this means the 2-inch display feels a little small, and we found the four-key interface to be a little awkward, but it didn't get in the way of figuring out how to diagnose your car.

The 56-inch cable is perfect to hanging over the hood while you work, and all BD310 itself is capable of performing action like an I/M inspection-readiness test or divulging performance details — including coolant temperature, engine timing and engine speed.

Read our full Ancel BD310 review.

More of the best OBD-II scanners

(Image credit: Tom's Guide)
Dependable, but comes with an annual subscription

Specifications

Display/size: None
Bluetooth/handheld: Yes/No
I/M Readiness test: Yes
Displays live data: Yes
Number of keys: None
Warranty: 1 year
Size: 3.1 x 2.0 x 1.1 inches
Weight: 2.7 ounces

Reasons to buy

+
Capable of reading enhanced codes
+
Lots of optional abilities on offer
+
Includes hard carry case

Reasons to avoid

-
$40 app subscription after 1 year
-
Heavy
-
Difficult installation 

The ThinkCar ThinkDiag TKD01 is one of the largest Bluetooth-based OBD-II scanners around, which can make it difficult to install. In fact the 3+ inch size means some cars may need to rely on an extension cable to plug this scanner in. But the upside is that the bulk makes the oval-shaped module more or less indestructible.

ThinkDiag's app offers profiles fore more than 100 automakers, which makes it ideal for locating manufacturer-specific error codes. This scanner is also able to show extended fault codes and can deal with errors like the oil-change light and monitor key car systems with minimal fuss. Like Innova the scanner is also able to predict when future problems may arise, but sadly doesn't offer any advice on how to deal with the issue.

Just be aware that your profile is only free for a single year, after which you'll need to pay an annual subscription fee of at least $40 to retain access.

Read our full ThinkCar ThinkDiag TKD01 review.

Best OBD-II scanners: Autel AutoLink AL539

Autel AutoLink AL539 (Image credit: Tom's Guide)
Ideal for diagnosing electrical problems

Specifications

Display/size: Color/2.8 inches
Bluetooth/handheld: Yes/no
I/M Readiness test: Yes
Displays live data: Yes
Number of keys: 8
Warranty: 1 year
Size: 6.7 x 3.6 x 1.4 inches
Weight: 10.6 ounces

Reasons to buy

+
Features electrics multimeter
+
Offers battery testing
+
Stand included

Reasons to avoid

-
OBD and electric scanners don't worj simultaneously
-
Battery needs charging

Autel's Autolink AL539 has a feature you don't often see among OBD-II scanners: A built-in multimeter that can uncover problems in your car's electrical systems. That includes burnt-out cables, electric shorts, alternator voltage, busted fuses and so on. The only major downside is that you can't use the multimeter while the AL359 is plugged in as an OBD-II scanner.

As an OBD-II scanner, the AL539 is able to show a range of live data, while also offering the ability to run a comprehensive pre-inspection readiness text. Any faults that are uncovered are displayed with red, yellow and green colored lights — green obviously meaning everything is a-ok.

The design also offers a great many benefits, particularly thanks to the compact and lightweight frame. However the AL539 also has a pull-out stand, which lets it stand on its own, and a generous 58-inch cable. We also found the interface to be very easy to follow, particularly thanks to the icons for all the major functions.

Read our full Autel AutoLink AL539 review.

Best OBD-II scanners: SeekOne SK860

SeekOne SK860 (Image credit: Tom's Guide)
Packing in a large color screen and a lifetime guarantee

Specifications

Display/size: Color/2.8 inches
Bluetooth/handheld: No/yes
I/M Readiness test: Yes
Displays live data: Yes
Number of keys: 8
Warranty: Lifetime
Size: 7.8 x 3.8 x 1.2 inches
Weight: 11.2 ounces

Reasons to buy

+
Lifetime warranty
+
Sturdy rugged design
+
Simple icon-centric navigation

Reasons to avoid

-
Large and heavy
-
Lacking features you'd find on other scanners

The SeekOne SK860 has a lot of great things going for it, including a large color screen, lifetime warranty, rugged design and the ability to perform a large number of tasks while also being easy to use. Of course you pay for all those benefits with a scanner that is both large and relatively heavy.

During our testing, we found that the eight-button navigation and an icon-based interface (packed onto a 2.8-inch color screen) made the SK860 incredibly easy to use. A lot easier than most budget scanners we've used in the past at any rate. Plus there's a single-button pre-readiness check to show you if there are any underlying faults.

Read our full SeekOne SK860 review.

(Image credit: Tom's Guide)
Inexpensive, but still reliable

Specifications

Display/size: Color/1.8 inches
Bluetooth/handheld: No/Yes
I/M Readiness test: Yes
Displays live data: Yes
Number of keys: 4
Warranty: Lifetime
Size: 4.8 x 2.6 x 0.9 inches
Weight: 6.1 ounces

Reasons to buy

+
Excellent value for money
+
Performs battery and I/M tests
+
Includes lifetime warranty and updates

Reasons to avoid

-
Interface is lacking
-
Missing some high-end features

The EDiag YA-101 is an inexpensive scanner that offers a large array of diagnostic features. This includes an I/M inspection-readiness test and a battery-testing sequence, all controlled by a color screen and a nice, intuitive interface.

That said, the low price does come with some caveats. There's no graphable data, no manufacturer-specific error codes or the ability to switch off those pesky oil-change lights. Likewise the 32-inch cable isn't quite long enough to reach under the hood of your car. 

But if you're looking for a way to get started with an OBD-II scanner on the cheap, this is still a reliable option to pick. Especially since it offers a lifetime warranty, and endless firmware updates.

Read our full EDiag YA-101 review.

How to choose the best OBD-II scanner for you

If you're looking for insights into how your vehicle is working or what's wrong under the hood, there's no better way than to plug in one of the best OBD-II scanners and read the results. 

After all, it's how your car dealer or repair shop would figure out what's wrong with your car when you drive (or are towed) in. Why shouldn't you have the same information?

Not all the best OBD-II scanners are created equal. There are two general types of devices.

Handheld OBD-II scanners come with their own screen and cable to plug into the car's OBD port. Wireless OBD2II scanners plug into the port, but then connect via Bluetooth to a smartphone or tablet to display their findings.

Whichever type you choose, there are several high-performance OBD-II scanners that cost less than $200. A couple are less than $30. What's important to remember is that the best OBD-II scanners provide the right mix of size, weight and the ability to read your car's fault codes and live data. The most important criteria are:

  • Easy setup. If it takes forever to set up the scanner, you probably won't use it to diagnose a problem early.
  • Faults and explanations. The best OBD-II scanners not only tell you the faults your car has but also can explain the meaning so you can either fix it yourself or tell a mechanic.
  • I/M Readiness check. A good scanner will run the major engine and emissions tests to see if you'll pass your state's inspection.
  • Accuracy. A scanner is worthless if its results aren't accurate, because the only thing worse than no information is incorrect information.
  • Size and weight. If the scanner is heavy and bulky, chances are it'll stay in your toolbox and not in the car to help you on the road.
  • Live data. By tapping into the car's engine speed, timing and other parameters, the right scanner can help track down an intermittent problem.
  • Graphs. Numbers are good, but a visual representation of it is much better, particularly if you're comparing before and after.
  • Warranty. You expect your car to last at least eight or 10 years, so why shouldn't your OBD-II scanner? That said, the best offer a lifetime warranty that should outlast your ride.

There's a gas tank full of criteria used to determine which OBD scanner is the best one for you. The most important is whether you want one that connects with your phone or tablet's screen over Bluetooth or a handheld unit with its own display and cable. 

Next, think about longevity and get one that includes lifetime warranty or software updates so the scanner will stay current with changing automotive tech. 

Then, how about screen size for a handheld scanner? Get the biggest, brightest and easiest display to read that is icon based for easy changes. If you're clumsy, look at rugged scanners with rubber bumpers to absorb the shock of being dropped.

Look for extras that are included on some models, like an electrical multimeter, the ability to read a manufacturer's proprietary codes or export documents as Acrobat PDF files. 

Finally, the price for these sophisticated devices is right on par with professional-level scanners that are available for under $100. That's barely an hour's labor for a qualified mechanic, making it a win-win purchase.

How we test OBD-II scanners

To test the best OBD2 scanners, I used my 2014 Audi A4 Allroad vehicle while it was in the garage or on the road over a period of several weeks. After connecting each scanner to my car's OBD-II port, I made sure they could report the car's vehicle identification number (VIN). 

For the wireless scanners, I connected to my Apple iPad Pro, Microsoft Surface or Samsung Galaxy S9+ phone via a Bluetooth or Wi-Fi connection. The handheld scanners only needed to be plugged into the OBD-II port, which provides power.

Next, I measured the cord's length on the handheld scanners and the wireless range on the others. With the car running, I monitored the engine and other vital systems, and then disconnected the engine's oil temperature sensor. 

Finally, I checked the details provided by the scanner, fixed the problem, turned off the check engine light and erased the error code.

Then I hit the road to see if the scanner could display operating data such as engine speed, timing and coolant temperature. I paid attention to whether the device reported the data as numbers, graphs or auto-style gauges.

Regardless of which OBD-II scanner you use, you'll need to crack its code. All fault codes have four numbers and a letter prefix:

  • Powertrain (P)
  • Body (B)
  • Chassis (C)
  • Undefined (U)

Of the roughly 5,000 diagnostic fault codes available, some are generic and apply to all cars, like air temperature and throttle position. For these, the numeric section starts with a 0. Others are specific to individual carmakers and represent either a special piece of hardware or a more in-depth analysis of the problem. These start with a 1.

For instance, if you get a P0098 code, chances are there's something wrong with the engine's intake air temperature sensor. By contrast, a Ford that displays a P1112 specialty fault code means that the intake air temperature sensor is reporting values intermittently and should be replaced.

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