I've tested all the Ninja products on sale for Prime Day — here's the 9 you should actually buy

One of Ninja's cheaper products, the Blast portable blender is impressively powerful. Sure, it can't compete with a full-size blender, but it did a great job of handling everything from protein powder to frozen berries when I put it to the test.

The Ninja Air Fryer Pro 4-in-1 is my top-rated air fryer for most people. It's a great compact air fryer that's got plenty of power, and I enjoy that despite its limited 5-quart capacity, it can cook up enough fries or wings for a whole family. And because of the 400°F top temperature, it's going to give you a delicious, crispy texture.

Ninja reinvented the air fryer game with its DualZone models, and the DZ201 is the largest of the bunch. With two 5-quart baskets, it can double up to make french fries for the whole family, or cook your main and your side simultaneously.

The Ninja Crispi is one of Ninja's most interesting recent releases. It features a removable cooking lid and interchangeable glass containers to cook meals of a range of sizes. And while I had my doubts, it blew me away in my Ninja Crispi review. In the end, I gave it a well-deserved 4.5 stars.

Want a does-it-all kitchen system? The Blender & Food Processor Combo has a 64 oz. max liquid capacity, and its 1500 watt motor is incredibly powerful. I tested the blender-only version of this combo, but I was a big fan, so this expanded edition with attachments for chopping and single-serve blending is bound to be even better.

The Ninja DoubleStack XL Air Fryer is one of Ninja's most innovative releases. This two-drawer air fryer saves a huge amount of counter space by stacking one drawer on top of another, doubling its cooking capacity for its footprint. It's got two drawers of 5-quart capacity, and comes with roasting trays to stack foods inside the drawers, too.

The Creami is famous for a reason. I use it all the time to turn everything from frozen yoghurt to homemade custard into tasty gelato. And if you're keen on increasing your protein goals, you can also freeze a shake and turn it into tasty, low-cal ice cream.

One of Ninja's best value options is this 14-piece knife set, and that's before this $90 discount. The set includes an in-built sharpener and even 6 steak knives. I've tried some market-leading knives in my years of testing, and this set from Ninja outperforms a lot of them.

Featuring 7 pans and 5 lids, this cookware set from Ninja has some of the best non-stick technology I've tried. You can use metal utensils while cooking and put these pans through the dishwasher without having to worry about flaking or damaging your pan. They're even oven-safe up to 500°F.