The short answer
The three air fryers in the specs dataset all publish exterior width, depth, and height. That means none of the three is excluded from this dimensions page for a missing footprint figure. The Ninja Crispi is the narrowest at 9.76 inches wide; the Cosori and Instant models are both 11.8 inches wide. Their depths and heights are close enough that the drawer shape and required clearance still matter more than width alone.
The figures come from manufacturer specifications and manuals represented in the existing specs dataset. Not published means the manufacturer does not publish that number in those source materials. We did not measure these appliances. The table is designed to help with a first counter check while keeping the manufacturer’s own missing data visible.
Cosori TurboBlaze
The Cosori TurboBlaze record gives an 11.8-inch width, 14.4-inch depth, and 11.9-inch height, including the handle. It publishes 5 inches at the rear. Its side and overhead clearances are not published, and its fully open drawer height is also not published. For that reason, the existing conservative fit answer is no: a safe overhead fit under an 18-inch cabinet cannot be confirmed.
That combination is a useful reminder that a small-looking height does not settle a cabinet question. The published footprint helps you reserve counter space, while the missing overhead and drawer-open fields stop the table from making a stronger claim than the manufacturer makes.
Instant Vortex Plus ClearCook
Instant publishes an 11.8-inch width, 14.9-inch depth, and 13-inch height for the ClearCook. The record says at least 5 inches above, behind, and around the sides. Its fully open drawer height is not published. The 13-inch body plus the 5-inch overhead requirement already reaches 18 inches, so the fit record answers no for an 18-inch upper cabinet.
Compared with Cosori, the Instant has a taller closed body and a more complete published clearance rule. Compared with the Ninja, it is wider and deeper. Those are published differences, not a claim about cooking performance. A reader choosing between them can use the same row to decide whether a permanent counter position is realistic.
Ninja Crispi
The Ninja Crispi record lists 9.76 inches wide, 11.5 inches deep, and 11.81 inches high. It publishes at least 6 inches at the rear, sides, and overhead. The fully open-height field is not published, and the record notes that the container is removable rather than a hinged drawer. The fit entry says yes under an 18-inch cabinet because the published height plus overhead clearance totals 17.81 inches.
The smaller footprint does not erase the clearance requirement. Keep the 6-inch published zone with the appliance rather than using the 9.76-inch width as the whole placement decision. The source link in the table is the place to check the exact model if the product changes.
What all three do not publish
All three air-fryer records leave the fully open drawer or container height as not published. That is 3 of 3 in this category. The missing value is not converted into an estimate from the closed height, a photo, or a similar model. It is displayed as Not published in the table.
The category does publish a useful amount of other fit information: all three have complete exterior dimensions, and all three publish an exterior capacity and wattage. The table keeps those facts separate from the open-height question so a published specification in one field does not imply publication in another.