Among the things NinjaKitchen “did right” in my never humble opinion, was to make the Inner Pots to their “original” Ninja Foodi appliance – The TenderCrisp units that combine an electric pressure cooker and air fryer the same diameter in all sizes 5 quart (4.7 litre), 6.5 quart (6 litre), and 8 quart (7.5 litre). I have been assured by Ninja Kitchen that the Width/Diameter of all FOODI inner pots outer diameter is approximately 10.5 inches (manufacturing spec is for centimeters)and the Inner Diameter is roughly 9.5 inches and, within the same size quart size (8, 6.5 or 5) are interchangeable. This seems to be true since the “replacement” part number is same for all current 8qt, etc., models. The same may be true for the Pressure Lid, but have not completely checked that so caveat emptor.

The chart below is drawn from several sources including the from the Amazon listings for the OEM inner pot stainless steel replacement pots offered on Amazon thru my affiliate store link for Foodi Friendly Accessories Using OEM inner pots may void your warranty. And even occasionally a response from Ninja Kitchens (the tidbit about usable height of the inner pot)

Ninja Foodi Inner Pot Measurements
These are in US Imperial Inches – so not completely exact – product produced in China are usually Metric so there may be slight variations in actual size, but these are what you will see when shopping.
Notes:
Abbreviations used: Apx=Approximate . D=Diameter . H=Height
Useful – The convex air fry lid extends into the Inner Pot, please allow at least 1.5 inches of “head” space.
The concave Pressure Lid allows a bit more space, so 1 inch is normally sufficient.

Note: stainless “cooks” slightly differently, may require you to adjust time and temps for some recipes. My opinion is that it matters only when using “dry heat” (air crisp, broil, bake, etc) and seem to cook hotter so often less time is needed.

The official Ninja Foodi Inner Pot is some sort of metal with a non-stick coating. (UPDATE: July 2021: Recently came across an Amazon Q&A where Ninja Kitchens answered that the metal of Inner Pot of the PC/AF Foodi under the “ceramic” non-stick coating is Aluminum) At the time the original Foodi was introduced in the US, and for months before – users of other brands were asking for a similar finish. I almost felt sorry for Ninja Kitchens, because immediately Foodi users started asking for a Stainless Steel. It is a mystery why they choose not to offer it as an accessory – but when you leave a product vacuum, someone in China will fill it. I have all three sizes, from three different OEM S/S sellers, they all work just fine. Still, always keep in mind, may void your warranty. This might be reasonable, since an ill fitting inner pot will likely cause your appliance to fail to function correctly. (although there nonsense of only using their other accessories such as cake pans – is not. At the very least it would not be reasonable to hold Ninja Kitchen responsible for you success since Stainless “cooks” differently than coated just as they do in any other form such as bakeware to stove top pots and pans.

Ninja Foodi Inner Pots have two important measurements. First the obvious, is the outer dimensions. Unless they are correct, your Lids will not seal correctly, I have read of some who disagree – caveat lectorem. (reader beware)

The PRESSURE Lid is Convex which gives you almost an inch more head room and the AIR CRISP Lid is Concave – meaning the face of the Air Fry extends into the inner pot reducing the amount of room.

The available height is further reduced by the necessary use of a trivet so that further reduces the available height. It is my never humble opinion that the combination of the use of a trivet or rack is essential – others may disagree. I am just here to let you know what works for me

Equally critical is the Inner Diameter. Why? In my experience, unless there is at least a 1/4 inch on each side, you may not get the air/steam flow needed to properly prepare your recipe. I like a bit more room for best results with either wet or dry heat functions. . And of course as an avid “Pot In Pot” technique user, a proper height trivet is essential. As a result pretty much ALL the accessories I have KEPT InMySmallKitchen for use in Darth Vader (my 6.5qt original style foodi) have been 8 inches or less in diameter. I have been lucky to find several useful trivet devices that are only 1/2 inch in height so that allows deeper pot or pan in the Foodi PC/AC

Another important consideration are the lids. It is important to understand that while the Pressure Lid is convex, thus allowing a bit more height for your accessory, the Crisper Lid is concave and extends into the inner pot by just of an inch – so best to allow at least 1.5 inches of “head” room to be safe.

Gripe: about a 10-12 months ago I asked Ninja Kitchens what the metal was used under the ceramic coating. Since then I have periodically been repeatedly told to rest assured, an answer will be be given as soon as the escalation team has one.

Ending on a positive note: Darth Vader my 6.5qt original style Ninja Foodi is now more than two years old. Thanks to their keeping the Inner Pot the same diameter – If/When it needs to be replaced, with obvious exception of the inner pots – not only will the things I have kept for use in Darth Vader be transferrable, but will also work in an 8 quart should I decide to go bigger. And, if someone builds a better mousetrap – about 80% will also work in other brands 6 & 8 quart Pressure Cookers.

Note: upon doing some research, it seems that the purchase of a replacement base is NOT a good investment. It has a 90 day money back policy, but NO warranty so if it fails on day 91, you will have paid at least the 1/2 the cost of a new unit, but your money – your choice.

Added July2021: Although I deplore Ninja Kitchens support for anything except warranty/replacement handling – now that Darth is occasionally hiccuping (errors that usually precede the dreaded err 8) I continue to explore replacement options. Some friends in the food world who know me well have said I will not like any of the alternatives. So I am keeping my mind open, but watching closely to see ‘what develops’ ….

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Food Craft – Making and Methods