Choosing between the convenience of a gas-fired and the magic of a wood-fired pizza oven can be a difficult decision to make. Fortunately, the Ooni Karu 12 is a high-performance oven that excels in both realms. The top-selling, wood-fired option in a lineup of truly excellent ovens, the Karu is nearly as efficient in its wood-burning form as it is as a gas-oven, capable of reaching pizza stone temperatures above 750°F with a continuously stoked wood-fire. A simple conversion with an accessory gas burner transforms this oven into a more convenient gas-powered format, operating as efficiently — if not even slightly more so — than its brother, the Ooni Koda 12. The Karu is a welcome addition to the kitchen arsenal of any well-prepared chef.Editor's Note: The Ooni Karu 12 review was updated on February 14th, 2022, with more information on which products we recommend and additional comparisons between models.
Ooni Karu 12 Review
Pros: Well-insulated, easily broken down for transport, easily converted multi-fuel system
Cons: Heat-resistive stone takes long to preheat, soot buildup in oven chamber reduces efficiency
Compare to Similar Products
Ooni Karu 12
|Price||$399 List||$499 List|
$499.00 at Amazon
|$350 List||$399 List|
$396.99 at Amazon
$129.95 at Amazon
|Pros||Well-insulated, easily broken down for transport, easily converted multi-fuel system||Unbelievable heat retention, quick baking time, accurate integrated thermometer, multi-fuel system||Reasonably priced, large capacity, heavily insulated firebox, transformable design improves versatility||Fantastic crust quality, high-fire temperatures, compact and portable||Affordable, designed for a normal range oven, fast bake times|
|Cons||Heat-resistive stone takes long to preheat, soot buildup in oven chamber reduces efficiency||Expensive, heavy, wood-fire box is small||Bulky, heavy, slow to preheat||Steep learning curve related to control, prolonged cook times||Heat profile depends on oven, heavyweight|
|Bottom Line||A beautiful, portable option that offers the best of both the gas- and wood-fired worlds||Superior design precedes superior performance in this professional-grade oven made for the common cook||Top-notch cooking performance, output power, and versatility, all at a fraction of the cost of direct competitors||The brand that put portable pizza ovens on the map lives up to its name with outstanding performance||A heavy-duty carbon steel slab capable of serious heat transfer to make the best pizza you've ever experienced out of a normal oven|
|Rating Categories||Ooni Karu 12||Gozney Roccbox||BakerStone Original||Ooni Koda 12||NerdChef 3/8" Steel...|
|Cooking Performance (30%)|
|Output Power (30%)|
|Ease of Use (15%)|
|Specs||Ooni Karu 12||Gozney Roccbox||BakerStone Original||Ooni Koda 12||NerdChef 3/8" Steel...|
|Fuel Type||Gas, Wood (w/ conversion)||Gas, Wood (w/ conversion)||Gas||Gas||n/a|
|Power Output||15,350 BTU||14,330 BTU||25,000 BTU||13,648 BTU||n/a|
|Size of Firebox||135 cu. in.||156 cu. in.||n/a||n/a||n/a|
|Average Stone Temperature||736°F||748°F||732°F||733°F||686°F|
|Footprint||368 sq. in.||299 sq. in.||345 sq. in.||368 sq. in.||228 sq. in.|
|Maximum Pizza Diameter||12"||12"||13"||12"||14"|
Our Analysis and Test Results
Staying true to its Sanskrit namesake, which translates most directly to "maker," the Ooni Karu 12 is certainly an oven designed for the committed pizza maker. This multi-fuel system comes standard as a wood-fired oven — the natural choice of traditional Neapolitan Pizzaiuolo. With the right fire-tender at work, the ostensibly small wood-fire is capable of generating internal oven temperatures above 800°F, capable of turning your homemade dough and fresh toppings into 12" pizzas in as little as two minutes. But for those who prefer the convenience of a gas-fired oven over the slower pace of a wood fire, the 15,350 BTU accessory attachment will help you achieve those same extreme temperatures much faster.
Like all multi-fuel ovens, much of the cooking performance depends on the fuel type. While gas-power is lauded for its accessibility, the art of wood-fired cooking should certainly not be taken for granted. The Karu is first-and-foremost a wood-fired oven, with all of the allure and charm of a traditional Neapolitan-style oven, just in a miniaturized format. As a result, it will take more time and careful tending to build up a powerful fire in the 135in³ firebox. After 15 minutes, we were able to get the oven up to workable temperatures around 560°F, but it takes more like 30 minutes of loading and stoking to get the pizza stone to the ideal temperature of 750°F.
It is essential to keep the fire stoked in between firings; you should ideally give the oven three to five minutes in between pizzas to regain strength. Wood-firing is always going to take longer, but even when our stoking slacked and pizza stone temperatures fell to near 500°F, the Karu was still capable of turning out beautiful, golden-kissed crusts in less than four minutes. This process shifts with the gas conversion. Gas gives a consistent heat output that boosts internal temperatures to an average of 746°F and pizza stone temperatures averaging 736°F. At this level, you can expect pizzas to cook more on the order of two minutes, with similarly shorter reheat times as well.
Though it takes more effort, there is a good reason why the best pizza makers in the world have not made the shift from wood-fired to gas-fired ovens. Under the right conditions — à la under the guiding eye of a skilled fire tender — wood is actually capable of burning hotter than gas. While this may seem unreasonable to some, consider that a gas-powered oven is only as powerful as its burner, whereas a wood fire can be stoked as hot as the size of the firebox allows. These high temps are essential to attain a perfectly crisped crust in a matter of minutes.
As a result — plus the fact that our infrared thermometer only reads up to 800°F — it is tough to say just how hot the Karu is capable of burning in its wood-fired configuration. We will admit it is more challenging to maintain a rip-roaring fire without a dedicated fire manager, simply because the relatively small firebox can only handle so much fuel at one time and burns very efficiently. It is easier to quantify the output power of this oven with the gas-burner; with pizza stone temperatures above 730°F, this oven is right on par with the Ooni Koda 12 in terms of output power. We deemed the Koda one of the most powerful pizza ovens in this review.
We know it is becoming a common thread, but wood-fire power has a steeper earning curve. It will take more commitment — both in time and patience — to learn how to properly fire the Karu as a wood-fired oven. But to your benefit as an aspirant chef, this oven is designed with the best insulation of nearly any oven we tested, and certainly more so than any other wood-fired model in this review. The front door is supported by two inches of glass-reinforced nylon, and even the cover to the firebox sports nearly one inch of the same insulation. The design of this oven also promotes fantastic airflow, which circulates heat within this sealed chamber, redirecting only minimal amounts of smoke up and out of the chimney.
While these insulated components are key to retaining heat and maintaining the types of temperatures necessary to cook a Neapolitan-style pizza, both the front door and chimney are removed with the gas conversion, essentially turning the Karu into a duplicate of the Koda. Operating in its gas-fire form, the tantalizing rolling flame of the background wood fire is replaced with twin burners, which are somewhat reminiscent of a jet engine both in appearance and power. Like other gas-powered ovens, changing from wood to gas will also change your cooking style. It becomes more necessary to closely manage the extent of the heat output of the gas flames to ensure that your fresh toppings don't blacken before the rest of the pizza has a chance to cook.
Ease of Use
Like all other Ooni ovens, the Karu is exceptionally easy to set up, both out of the box and each and every time you plan on baking pizzas. While this kit contains more components — particularly in its wood-fired format — each part is removable, stripping the oven down to a practically portable stainless steel frame that weighs just over 20 pounds. The cleaning difficulty will likely change based on the type of wood you choose, but natural scraps produce more significant amounts of ash buildup inside the oven chamber that needs to be wiped away regularly to maintain cooking efficiency through reflective heat transfer.
But as we all know by now, wood-firing will always take more effort than firing up a gas-powered oven, both in terms of wood preparation and cleaning. It certainly is possible to learn how to manage the wood fire while simultaneously prepping pizzas, but converting the Karu to gas will simplify this process by allowing you to preheat the oven with a literal flick of a switch. But in our humble opinion, running a gas-powered pizza oven will never quite compare to the sensational event of making wood-fired pizzas.
Should You Buy the Ooni Karu 12?
Whether in its gas-powered or wood-burning form, the versatility and cooking performance of the Ooni Karu 12 is sure to please everyone, from aspiring pizza makers to top-level chefs. The capabilities of this multi-fuel oven necessitate some commitment to learning the craft of the Pizzaiuolo. Still, as you discover the tricks of the trade, you can expect to be rewarded with delicious Neapolitan-style pizza every time you fire up this incredible oven. We recommend this pizza oven to anyone who wants a smart-looking and portable option with flexibility in fuel type.
What Other Pizza Ovens Should You Consider?
The excellent performance of the Karu, even in its standard wood-burning form, translates to a higher price tag than other similar options. Although the gas burner is an accessory purchase, it is more than worth the additional cost to unlock the full potential of this fantastic pizza oven. If the price seems a bit steep, you may want to look at the BakerStone Original. Although it is a bit bulky and does not have the option for wood fire heat like the Karu, it still performs on par with top competitors and is much more affordable. The NerdChef 3/8" Steel Stone is another product that we consider a great value with above-average performance. It is used in conjunction with a standard oven and is good for households with an overabundance of appliances.
— Aaron Rice
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