Ninja
Foodi Dual Zone Series
Dual zones excel, but bulky with small baskets.

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Id definitely go with the Instant vortex mini. its around $60 and is the recommended budget air fryer on wirecutter. You can find some good options [in this thread](https://www.reddit.com/r/cookingforbeginners/comments/1lxgrty/best_budget_air_fryer/)
I like Ninja, but if you want a small one, I highly recommend Instant Pot Vortex 2-QT Mini.
Tht's similar to the Instant Pot Vortex 2QT Mini Air Fryer I have. I use it all the time, instead of my larger Ninja, simply because I air fry very little food at a time.
We are quite happy with the Instant Pot Vortex 2QT Mini Air Fryer
I’m guessing most people buy larger air fryers given the comments. The instant mini is only 8” as well. I love it.
Don’t buy Instant Pot. I got their Vortex Mini model, and used it almost daily for about two years. The basket developed a small hole on it, due to rubbing when it’s inserted/removed (which is a design flaw in my opinion). I contacted them to get/purchase a replacement basket, since the rest of the device functions just fine. They told me that particular model is discontinued, and they can’t get me another basket.
I’ve use a Insta Pot 2 quart air fryer. It worked great for me for 5 years. I just replaced with a 5 quart Ninja. Besides being larger which is no biggie cause it’s just me, I have problems with stuff blowing around in the Ninja which wasn’t an issue with my Instant Pot AF. Also, the old Insta Pot AF had a roast option. I noticed most but not all portable models, no matter the brand, replaced the bake option with dehydrator. Perhaps there are folks who do dehydrate, but I personally don’t know anyone interested in such a feature. I’m thought about gifting the Ninja and going back to a Insta Pot AF EXCEPT the model Ninja I have has a ceramic coating which I love and is supposedly healthier than Teflon.
Ninja
Foodi Dual Zone Series
Dual zones excel, but bulky with small baskets.

COSORI
Turbo Blaze 9-in-1 6QT
Effortless to clean and quiet, but no viewing window.

Ninja
Foodi Air Fry Oven Series
Unique flip design, but shallow and air frying debated.

Typhur
Dome
Self-cleaning and quiet, but expensive with shallow interior.

Breville
Smart Oven Air Fryer Series
Great oven replacement with large capacity, but poor air frying.

Ranked #1
Ninja - Crispi Pro 6-in-1 Countertop Glass Air Fryer

Ranked #1
Breville - Smart Oven Air Fryer Series

Ranked #1
COSORI - Turbo Blaze 9-in-1 6QT

Ranked #1
Ninja - Crispi Pro 6-in-1 Countertop Glass Air Fryer

Ranked #1
Ninja - Foodi Air Fry Oven Series