The model number on your Ninja can be found in a few different places, depending on the model and style of the machine. For older models, the model number is typically located on the bottom of the unit near the power cord. For newer models, the model number can be found on a sticker inside the food processor bowl or on a label affixed to the back of the unit. If you're having trouble finding your model number, you can also check your owner's manual for more information.