Heat Comes From the Grill, Not the Best Pizza Oven for Gas Grill

Affiliate Disclosure: As an Amazon Associate, we earn from qualifying purchases. This does not affect the price you pay.

A grill-top pizza oven has no burner, no element and no fuel line. It is a steel box with a stone in it, and every degree it reaches is borrowed from the grill underneath. That single fact decides how to read every listing on this page.

Seven of these ten publish no maximum temperature at all. Of the three that do, two are quoting the range of a dial. Cuisinart’s thermometer “tracks oven temperature up to 800°F”, and Skyflame’s adjustable box carries a gauge whose range “can reach up to 800F”. Only one listing makes a heat claim about the oven itself — Onlyfire’s 700°F in 15 minutes — and that model does not sit on a grill grate at all.

The silence is mostly honest. A box cannot promise a temperature when it does not know what is under it. A small two-burner grill and a large six-burner grill put very different amounts of heat into the same piece of steel, and a charcoal kettle is different again.

So the numbers that matter are the ones a maker can control. Which grills does it say it fits — gas only, or gas, charcoal and pellet? How big is its footprint against your grate, and how tall is it against your hood? What is the stone, and does the listing give its size? Is there a thermometer, and what is actually in the box?

On those questions the ten split sharply. Nine include a thermometer. Seven include a peel. One — Skyflame’s adjustable cover — mentions no stone anywhere in its listing. Only CAMPLUX publishes its stone in both dimensions, 14.8 by 13 inches. Published footprints run from 16.3 by 14 inches to 22 by 15, and one design stretches from 20 to 30 inches wide to fit the grill it sits on.

One product here is not a grill-top oven. The Onlyfire side-burner model is built to sit over the single side burner many gas grills carry, and it measures 10.8 by 12.4 inches. We have kept it in, and we treat it as the different category it is.

The most-reviewed oven here is the CAMPLUX, and the best-ranked is the Geras.

Our Quick Picks

At a Glance

Ten Grill Ovens, Sorted by What They Say They Fit

Read the first two columns against your own grill before anything else. A blank temperature is normal here: the burners under the box set it.

#	Model	Grills Stated	Footprint	Max Temp	Best Sellers Rank	Standout	Main Drawback	Check Price
1	Cuisinart CPO-700	Gas, charcoal, pellet	16.3 × 14 in	800°F (thermometer)	#6,700 in Outdoor Cooking Tools & Accessories	Broadest stated fit in a compact 16.3 by 14 box	Stone size not stated anywhere in the listing	View on Amazon
2	Skyflame Stainless 22×15	Gas, pellet; kamados named	22 × 15 in	Not stated	#134 in Pizza Grilling Stones	4.4 across 146 ratings, stone and thermometer	22 inches long; no peel listed in the box	View on Amazon
3	CAMPLUX PZ17B	Propane, charcoal	17.3 × 13.9 in	Not stated	#243 in Outdoor Ovens	14.8 × 13 in stone, the only one fully dimensioned	No peel; 6.8 in tall, the tallest box here	View on Amazon
4	Onlyfire Stainless Flip-Lid	Gas, charcoal, pellet	17 × 17 in	Not stated	#69 in Outdoor Ovens	All-stainless chamber with a flip-open lid	“Wood-fired temperatures” with no number attached	View on Amazon
5	BakerStone Basic Series	Grill top; propane named	16.3 × 14 in	Not stated	#55 in Outdoor Ovens	Stone on five sides; 2–4 minute bake stated	Charcoal and pellet never mentioned; ratings pooled	View on Amazon
6	Geras HeatGuard Pro	Gas, charcoal, pellet, wood	16.93 × 17.72 in (as listed)	Not stated	#19 in Outdoor Ovens	#19 in Outdoor Ovens, the best rank here	Listing calls it both 12-inch and 15-inch	View on Amazon
7	Skyflame Adjustable Metal	Gas, pellet	20–30 × 16.5 in	800°F (gauge range)	#164 in Outdoor Ovens	Base adjusts from 20 to 30 inches wide	No stone mentioned anywhere in the listing	View on Amazon
8	Jcrisova 12-Inch Grill Oven	Gas, charcoal	16 × 14 in	Not stated	#57 in Outdoor Ovens	Stone, peel and thermometer, lowest-priced box	4.5 rating rests on only 14 ratings	View on Amazon
9	Templeton Pizza Oven Topper	Not specified	Not stated	Not stated	#232 in Pizza Grilling Stones	Viewing window, plus peel and cutter included	No grill type or dimension published at all	View on Amazon
10	Onlyfire Side Burner Oven	Side burner only	10.8 × 12.4 in	700°F stated	#203 in Outdoor Ovens	The only oven-temperature claim on the page	Useless without a side burner; 3.9 across 49	View on Amazon

Ratings and specifications are taken from each manufacturer’s Amazon listing as displayed on 5 October 2026 through a United States connection, and may change. Max Temp is mostly blank by design. A grill-top box generates no heat, so its ceiling is your grill’s. Where a figure appears we say what it describes: Cuisinart’s and Skyflame’s 800°F are thermometer ranges (Cuisinart’s description also says the oven “reaches” it), and Onlyfire’s 700°F belongs to a side-burner unit, not a grill-top box. Footprints are as published and some conflict: Geras lists 16.93"D × 5.51"W × 17.72"H, which reads like a height in the width column; Skyflame’s adjustable cover gives 16.5 in deep in its bullets and 20 × 18 in in its spec table; Jcrisova gives 16 × 14 × 4.5 in in its bullets and 14 × 15 × 4 in in its spec table. BakerStone’s 4.2 across 308 ratings is pooled with its separate propane listing, which shows the identical count and rank. Sales ranks are shown as displayed and sit in different categories, so compare them with care.

Scroll the table sideways to see every column

How We Chose These Ten

We researched current listings, compared manufacturer specifications and documentation, and examined recurring patterns in customer feedback. We did not carry out hands-on testing, and nothing below is presented as measured performance data.

• Stated grill compatibility first — gas only, gas and charcoal, or gas, charcoal and pellet, exactly as each listing words it
• A published footprint and height, or a note that none exists — a box that does not fit your grate is not an oven, and one listing gives no dimension at all
• The stone, its material and its size — five name cordierite, one says ceramic, one lines five sides with stone, and one mentions no stone
• A thermometer, and what its number means — nine have one; we separate a dial’s range from a claim about the oven
• What arrives in the box — seven include a peel, one adds a cutter, one a turning peel, one a storage bag
• A verified live buy box — all ten confirmed purchasable with United States delivery on 5 October 2026
• One review pool, counted once — BakerStone’s propane version shares its 308 ratings with the grill-top box, so we kept the grill-top box and dropped the duplicate

The Ten Grill Ovens in Detail

Seven of Ten Never Say How Hot They Get

In a self-fuelled pizza oven, the maximum temperature is the headline specification. In this category it is mostly absent, and the reason is the whole point of the product: the box burns nothing. Here is every temperature, preheat and bake figure the ten listings publish.

The one oven-temperature claim belongs to the one product that is not a grill-top box. Onlyfire’s side-burner unit can state 700°F in 15 minutes because it is designed for a single, known heat source. The two 800°F figures on grill-top boxes are the scale of a dial: they tell you the gauge will not peg before you reach pizza heat, not that your grill will drive the box there. Cuisinart’s description does say the oven “reaches up to 800°F”, and we report it, but it is a claim only your burners can keep.

The bake times spread from 2 to 15 minutes, and the spread follows construction, not price. The fastest stated bake, BakerStone’s 2–4 minutes, comes from the only box with stone on five sides. The slowest, Skyflame’s 8–15, comes from a box designed to be used with the grill hood open. In between sit Cuisinart’s reflective stainless interior at 5–7 and the Templeton at 8–10. The pattern is about top heat. Every box on a grate gets plenty of heat from below; what separates them is how much reaches the top of the pizza, and stone or reflective steel overhead is how a box without a flame of its own gets it there.

Only two grill-top listings publish a preheat, and both are honest about it. BakerStone gives 10–15 minutes and adds that it “may longer in rain/cold”; Jcrisova gives 15–20 minutes to heat the stone. Neither is a long time by pizza-oven standards, but both are the real cost of the first pizza. A two-minute bake after a fifteen-minute preheat is a seventeen-minute pizza the first time and a two-minute pizza after that.

Fit Is the Specification That Decides It

A grill-top oven has to sit flat on your grate, leave room around it for hot air to rise past, and — if you cook with the hood down — fit underneath the hood. Here is what each listing gives you to check that.

Three listings tell you to measure, and they are the three you can measure against with confidence. Onlyfire’s stainless box says “Please measure your cookbox before ordering”, Skyflame’s adjustable cover says to measure the grill chamber, and Jcrisova says to measure your grill grate. Each also publishes the figure to measure for. The Templeton, by contrast, gives you no footprint and no height at all.

The footprints cluster tightly and then jump. Five boxes sit within a couple of inches of 16 by 14 to 17 by 17. Then Skyflame’s stainless box runs to 22 inches, and its adjustable cover starts at 20 and needs a grill larger than that. A box that fits a large three- or four-burner gas grill comfortably may not sit on a compact two-burner model at all. The smaller the grill, the more the 16.3 by 14 boxes from Cuisinart and BakerStone, and Jcrisova’s 16 by 14, make sense.

Height decides whether you can close the hood. Most boxes here are 4.5 to 5 inches tall. CAMPLUX is 6.8. If you want the hood down to trap heat around the box, measure from the grate to the lowest point of the closed hood and leave room for the thermometer; if you plan to cook hood-up, as both Skyflame designs intend, height matters far less.

The fuel lists are worth reading word for word. Cuisinart and Onlyfire name gas, charcoal and pellet. Geras adds wood. CAMPLUX names propane and charcoal and leaves out pellet; Jcrisova names gas and charcoal; Skyflame’s adjustable cover names gas and pellet. BakerStone calls itself a propane and gas oven and mentions nothing else. None of this means a box will fail on an unnamed grill, but on a page where some makers state all three, silence about yours is a reason to choose one that does.

Stone, Thermometer and What Arrives in the Box

The grill supplies the heat. The stone is what turns it into a crust, and the thermometer is how you know whether the grill is doing its job. Here is what each listing says it includes.

Nine of ten mention a stone; one gives its size in both dimensions. Cordierite is named by five, which is the material you want for repeated heating and cooling. CAMPLUX alone gives a full 14.8 by 13 inches; Jcrisova gives 12 inches; BakerStone gives 12 inches for the oven. Everyone else leaves you to discover the size when it arrives. Skyflame’s adjustable cover, alone, mentions no stone at all.

Nine have a thermometer, and on a grill-top box it matters more than on a self-heating oven. A self-fuelled oven has a burner you can turn up against a known target. Here the dial is the only way to know whether your grill is driving the box hot enough, because the maker could not tell you in advance. The side-burner unit is the only one with no thermometer listed, and the Geras mentions one only in its spec table.

Seven include a peel, and the three that do not are among the better-equipped otherwise. CAMPLUX ships a bag instead; both Skyflame listings ship without one. A peel is not optional for a box with a low front opening — the pizza has to go in on something — so budget for one if your choice is in that group. BakerStone is the only kit with a turning peel as well as a launching peel.

The Side Burner Oven Is a Different Product

The Onlyfire side-burner unit appears in the same searches and shares a brand with one of the grill-top boxes, but it answers a different question. Here is the difference in one table.

The side-burner oven trades size for independence. It cannot bake the 12- and 13-inch pizzas the grill-top boxes quote, because the whole unit is 10.8 by 12.4 inches. But it can bake while burgers are on the main grate, and it is the only product on this page with a stated oven temperature. If your grill has a side burner you rarely use, it is the cheapest way to put that burner to work. If it does not, it is not an option at all.

Best Alternatives

A grill-top box is one of several ways to make pizza with fire outdoors. These are the options worth weighing against it.

If you find you want a published temperature and a burner of the oven’s own, our pizza oven guide compares self-fuelled ovens from 700°F to 1110°F, and that is a genuinely different purchase from anything on this page.

What Each Step Up Actually Buys

Lowest-priced tier — Onlyfire Side Burner. A different category at the bottom of the range. It buys the only stated oven temperature on the page, 700°F, and a free main grate, at the cost of a small footprint and no thermometer.

Entry tier — Jcrisova, Templeton, Skyflame Adjustable, Skyflame Stainless. The most uneven. The Jcrisova buys a complete kit on a 14-rating sample. The Templeton buys a window and a cutter but no published dimension. Skyflame’s cover buys adjustable width and no stone. Skyflame’s stainless box buys the best-rated sizeable sample here, 4.4 across 146, if your grill takes 22 inches.

Established tier — CAMPLUX, Cuisinart, Onlyfire Stainless, Geras. Review counts run from 215 to 877. The step up buys documented fit — three of the four name gas, charcoal and pellet or more — and in CAMPLUX’s case the only fully dimensioned stone. Cuisinart is the most complete set of answers to the questions that decide a grill-top oven.

Premium tier — BakerStone Basic Series. The top of the range buys construction: stone on five sides, 26 lb of it, a 2–4 minute stated bake and two peels. It is the only step up on the page that buys a different way of building the oven rather than a better-documented version of the same box.

What to Check Before You Buy

Measure Your Grate in Both Directions

This is the first check and the one most often skipped. Measure the usable cooking area side to side and front to back, then compare both figures with the box. The published footprints here run from 16 by 14 inches to 22 by 15, and Skyflame’s cover needs a cooking area larger than 20 by 16.5 inches. A square 17 by 17-inch base, like Onlyfire’s, needs 17 inches front to back, which is often the shorter dimension on a gas grill. Leave some space around the box rather than filling the grate edge to edge: the box is heated by burner heat rising past and under it, and a box that blocks the whole grate also blocks the flow. Three listings on this page tell you to measure first. Treat that as advice for every one of them, and treat a listing with no dimension, like the Templeton’s, as something to measure on arrival before the return window closes.

Measure the Hood Clearance

If you intend to cook with the grill hood closed, the box has to fit underneath it. Measure from the grate to the lowest point of the closed hood — often near the front, where the lid curves down — and compare it with the box height plus anything that sticks up, such as a thermometer dial. Most boxes here are 4.5 to 5 inches tall; CAMPLUX is 6.8 inches. Both Skyflame designs are intended for hood-open cooking, so their height matters much less. If a box will not fit under your closed hood, you can still use it hood-up, but you lose the heat the hood would have trapped around it, and a box designed for hood-closed use may bake its tops more slowly as a result.

Match the Fuel List to Your Grill

Read the bullets, not the spec table. On this page the spec tables say “Propane” for the Geras, “Wood” for Skyflame’s cover and Onlyfire’s side burner, and “Charcoal” for the Jcrisova, and each contradicts its own bullets. The bullets are where makers actually say what they designed for. Cuisinart and Onlyfire’s stainless box name gas, charcoal and pellet; Geras adds wood; CAMPLUX and Jcrisova name gas or propane and charcoal; Skyflame’s cover names gas and pellet; BakerStone names only gas and propane. If you own a pellet grill, or might switch to one, choose from the listings that name it. If you only ever cook on gas, the whole page is open to you.

Find Out Whether There Is a Stone, and How Big

The stone is the working part of a grill-top oven. It sits between the burners and the dough, stores heat, spreads it out so the base does not scorch over each burner, and draws moisture out of the dough so the crust crisps instead of steaming. Nine listings here mention one; Skyflame’s adjustable cover does not mention one anywhere. Only CAMPLUX gives full dimensions, 14.8 by 13 inches, and states the pizza size that fits, 13 inches. Jcrisova says 12-inch; BakerStone says its oven is 12"; the Geras says both 12 and 15. Cordierite, named by five listings, is the usual choice for stones that are heated and cooled repeatedly. If a listing gives no size, plan for a 12-inch pizza and be pleased with anything larger.

Treat Any Temperature as the Dial’s, Not the Oven’s

A grill-top box generates no heat, so no listing can honestly promise how hot it gets on your grill. The two 800°F figures on grill-top boxes here are thermometer ranges — Cuisinart’s dial “tracks oven temperature up to 800°F” and Skyflame’s gauge has a range that “can reach up to 800F”. That is useful, because a dial that topped out lower would peg before you reached pizza heat, but it tells you about the scale, not the grill. The same caution applies to the side-burner unit’s 2200°F stone rating, which is a tolerance, not a cooking figure. What you will actually reach depends on how many burners you have, how hard they run, whether the hood is closed and, as BakerStone admits, the weather.

Count What Is in the Box

Seven of the ten include a peel; CAMPLUX and both Skyflame listings do not. A grill-top box has a low front opening, so the pizza has to go in on a flat, thin peel, and you need it before the first bake. If your choice ships without one, our pizza peel guide explains why wood launches better and metal retrieves better. BakerStone is the only kit here with a turning peel as well, which matters because the burners under a box are rarely even and the side nearest the hottest one will brown first. Templeton adds a pizza cutter and CAMPLUX a storage bag. Price the missing pieces in before comparing the totals.

Know Whether You Will Cook Hood Open or Closed

The designs on this page split into two approaches. Skyflame’s stainless box and adjustable cover both state that they are meant to be used with the grill hood open: the box itself is the oven, and you can watch the pizza the whole time. That is convenient, and it means hood clearance does not matter, but the box has to hold all the heat on its own, and Skyflame’s 8–15 minute stated bake reflects that. Other listings do not say either way. A box under a closed hood benefits from the heat the hood traps around it; a box in the open does not. Decide how you want to cook, then check the height, the stated bake time and whether there is a flip lid or a window that lets you look without lifting the hood.

Common Mistakes

• Buying a box without measuring the grate. Footprints here run from 16 by 14 to 22 by 15 inches.
• Forgetting the hood. One box is 6.8 inches tall; measure to the lowest point of the closed lid.
• Reading 800°F as a promise. On both grill-top boxes that print it, it is the dial’s range.
• Assuming every listing includes a stone. One of the ten never mentions one.
• Trusting the spec table over the bullets. Four spec tables here contradict their own fuel claims.
• Buying the side-burner oven for a grill without a side burner. It has no other use.
• Forgetting the peel. Three of ten ship without one, and the first pizza needs it.
• Trusting a 4.5 rating on 14 ratings over a 4.3 on 554. One review moves the small one.

Who Should Buy Which

Buy the Cuisinart CPO-700 if you want the safest all-round answer. Gas, charcoal and pellet are named, the 16.3 by 14-inch box fits smaller grills, the cordierite stone and 800°F thermometer come with it, and 4.3 across 554 ratings is a meaningful sample.

Buy the Skyflame Stainless 22×15 if you own a large grill and like to watch. 4.4 across 146 ratings, a stainless housing, stone and thermometer — and a design meant for hood-open cooking. Measure for 22 inches first and buy a peel.

Buy the CAMPLUX PZ17B if pizza size matters most. Its 14.8 by 13-inch stone takes up to a 13-inch pizza, and 877 ratings at 4.3 is the largest sample here. Check hood clearance against 6.8 inches and budget for a peel.

Buy the Onlyfire Stainless Flip-Lid if your grate is deep and you want to see the top. A 17 by 17-inch stainless chamber, a lid that lifts to show the whole pizza, and stone, peel and thermometer included.

Buy the BakerStone Basic Series if you cook on gas and want the fastest bake. Stone on five sides and a 2–4 minute stated bake, with two peels. It weighs 26 lb and never mentions charcoal or pellet.

Buy the Geras HeatGuard Pro if you trust the market’s verdict. It is the best-ranked oven here, with a broad fuel claim, but measure it on arrival: the listing calls it both 12-inch and 15-inch.

Buy the Skyflame Adjustable Metal if your gas grill is at least 20 inches wide and you already own a stone. It is the only design here that adjusts to the grill, from 20 to 30 inches.

Buy the Jcrisova if you want to try grill-top pizza for the least money. Stone, peel and thermometer in the smallest published box here — on a 14-rating sample.

Buy the Templeton only if the window is the point. No other oven here lets you watch without opening something, but no dimension or grill type is published.

Buy the Onlyfire Side Burner only if your gas grill has a side burner you want to put to work. It keeps the main grate free and states 700°F in 15 minutes.

Frequently Asked Questions

Final Verdict

A grill-top pizza oven borrows every degree it has from the grill underneath. That is why seven of these ten publish no maximum temperature, and why the two 800°F figures on grill-top boxes turn out to be dial ranges. The only oven-temperature claim on the page, 700°F in 15 minutes, belongs to the one product built for a single known burner — and it is not a grill-top box.

So the specifications that decide this category are the ones a maker can control. Which grills it names. How big it is against your grate and how tall against your hood. Whether there is a stone, and how big. Whether there is a thermometer to tell you what your grill is doing. Whether a peel is in the box. On those, the ten differ far more than on anything printed in degrees.

Construction, not price, sets the bake time. Stone on five sides gives BakerStone a stated 2–4 minutes; an open-hood design gives Skyflame 8–15. In between, Cuisinart’s reflective stainless interior states 5–7.

If you buy one oven for a gas grill from this page, make it the Cuisinart CPO-700 — the broadest stated fit in one of the smallest boxes, a cordierite stone, a thermometer and a peel, on 554 ratings. Measure your grate first.