How large does an oven need to be to fit a 18 lbs turkey?

The oven in a standard 20" kitchen stove will accommodate a bird even as large as 20 lbs (9 kg).

The very detailed chart here, the pertinent details of which are replicated in the chart below, establish the standard dimensions of such an oven as 18 X 16 X 14.5 inches (46 x 41 x 37 cm).

In their downloadable Thanksgiving pdf, for a turkey as large as 20 lbs (9 kg) Williams-Sonoma recommends a 16 X 13 X 3 inch (40 x 33 x 7.5 cm) roasting pan. A pan of this sort is available with a rack which rises just above the bottom of the pan, as here and pictured below.

This kind of pan keeps height requirements down to roughly the height of the bird plus 3" (7.5 cm) above the bird, plus the standard 2.5" (6.5 cm) below the bottom rack. With 14.5" (37 cm) worth of oven height to work with and about a half inch space between the bird and the pan, that still leaves room for a bird 8" (20 cm) tall. (We won't expect the bird to be half as tall as the pan is long.) Meanwhile, an 18" (46 cm) oven depth accommodates a 16" (41 cm) long pan, and a 16" (41 cm) oven width a 13" (33 cm) pan width. Also, as seen here and below, the pan's handles fold down.

Now, none of this is to say that there's anything the slightest bit convenient about roasting so large a bird in so small a space. But it can be done. It should just be done with every whit of safety in mind.

MetroKitchens suggests that for a 17-20 lb bird, you need a roasting pan that is 16 x 13 x 3 inches (about 41 x 33 x 8cm). The oven will need to be taller than the pan, because a turkey sticks out above a roasting pan, but you can reduce that considerably by spatchcocking the bird. I'm bad at estimating visually, but I think it'd be around 6-10 inches (15-25cm) tall when spatchcocked. You also will want some headroom to avoid having the heating element too close to the bird if you have a heating element on top, or else to avoid having the bird brush up against the oven if your heating element is located elsewhere.

So this large-capacity toaster oven might barely work, as it is 10.35 H x 18.19 W x 15.39 D, but I wouldn't go much smaller.

General Electric (http://products.geappliances.com/appliance/gea-support-search-content?contentId=18680) says:

• A 30" Freestanding Range will hold a turkey about 24-26 lbs.

• A 30" Freestanding Double Oven Range (lower oven) will hold a turkey about 20 lbs. Note: The turkeys we test are normally in the 20-25lb range, and in those cases we use the lower oven of the double oven. We do not have any information on turkey sizes for the upper oven, nor do we recommend cooking whole turkeys/chickens/hams in the upper oven.

• A 30" wall oven (convection or conventional) will hold up to a 35 lb. turkey. Note: For 30" Single/Double Wall Ovens, it is recommended to go by turkey size rather than weight. Check oven interior dimensions by model.

• 27" and 24" built-in ovens will hold a turkey approximately 22-23 lbs. A larger bird may be accommodated depending on the shape of the bird.