Quick Answer: Most pizza ovens use a round deck to match their dome shape, but a genuine square pizza oven does exist — the Ooni Koda 16 ($499, clearance) bakes on a real 16 x 16-inch square cordierite stone instead of a circle, per Ooni’s own spec. If you’d rather convert a grill you already own, the BakerStone Pizza Oven Box ($139.99-$159.99) is a rectangular 5-sided stone chamber that sits on any grill’s grate. Already own a Camp Chef 14-inch stove? The Camp Chef Artisan Outdoor Oven accessory ($179.99) is a rectangular 14 x 16-inch box built for it.

Search for “square pizza oven” and you’ll get two very different kinds of results: a handful of standalone ovens that genuinely use a square or rectangular cooking stone, and a separate category of box-shaped accessories that clip onto a grill or camp stove you already own. Here’s what actually fits each shape, and why the deck shape is worth caring about at all.

Square and rectangular pizza ovens, by the numbers

Square & rectangular pizza ovens at a glance

OvenBest forDeck / chamberMax tempPrice
Ooni Koda 16Best standalone square oven~16" x 16" square stone~950°F~$499 (clearance)
BakerStone Original Series Pizza Oven BoxBest grill-top conversion15" x 13.75"~800°F~$139.99-$159.99
Camp Chef Artisan Outdoor OvenBest for Camp Chef stove owners14" x 16"~600°F+~$179.99

Best standalone square oven: Ooni Koda 16

Ooni Koda 16 (1st Generation, clearance)

Best standalone square oven · ~$499 (was $649)
  • Genuinely square ~16 x 16-inch cordierite stone, per Ooni's spec — not a round deck squeezed into a 16-inch circle.
  • The extra corner area over a round 16-inch deck fits a rectangular Detroit-style or Sicilian pizza, or two smaller pies side by side.
  • L-shaped gas burner reaches ~950°F, folds flat, and is now selling as first-generation clearance stock at ~$499.
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For the full sizing breakdown against Ooni’s other models, see our pizza oven dimensions guide, or our best pizza oven under $1000 roundup for how the Koda 16 stacks up against premium picks.

Best grill-top conversion: BakerStone Original Series Pizza Oven Box

BakerStone Original Series Pizza Oven Box

Best grill-top conversion · ~$139.99-$159.99
  • Rectangular 5-sided stone chamber — stone on the top, sides, and bottom — traps heat around the pizza instead of just underneath it.
  • Sits directly on any gas or charcoal grill's existing grate, so there's no separate burner, tank, or fuel to manage.
  • 15 x 13.75-inch interior fits a full round pie or a rectangular sheet-pan pizza equally well.
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If you already own a grill you like, this is the cheapest way into pizza-oven territory — see our full BakerStone pizza oven review for tested results and which grills it fits best.

Best for Camp Chef stove owners: Camp Chef Artisan Outdoor Oven

Camp Chef Artisan Outdoor Oven

Best for existing Camp Chef stove owners · ~$179.99
  • Rectangular 14 x 16-inch ceramic stone accessory built specifically for Camp Chef's 14-inch two-burner stove system.
  • Preheats in about 15 minutes and exceeds 600°F, per Camp Chef — enough for a solid New-York-style bake.
  • Only makes sense if you already own (or plan to buy) the compatible Camp Chef stove — it isn't a standalone oven.
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We cover exactly how this accessory differs from Camp Chef’s standalone Italia Artisan oven in our Camp Chef pizza oven review — don’t buy this one without checking which setup you actually have.

Why the deck shape actually matters

A round deck matched to a dome oven isn’t a flaw — Ooni, Gozney, and Solo Stove all build around it because a round chamber reflects radiant heat evenly back onto a round pizza as you rotate it. The case for square or rectangular decks is narrower but real: if you regularly bake Detroit-style, Sicilian, or sheet-pan pizzas that are naturally rectangular, a round stone the same width wastes the corners that a square one gives you for free. And if you already own a grill or a Camp Chef stove, a box-style accessory gets you into pizza-oven cooking for well under $200 without a second fuel source to manage. For most buyers who only care about round pizzas and top-end heat, a standard round-deck oven from our best outdoor pizza oven guide is still the simpler choice — square decks are a real but situational upgrade, not a strictly better shape.