Listed size and fitting size are different numbers
Most consumer totes are described by a nominal capacity and a rounded body size. The number that decides whether it fits is the largest outside dimension including everything that sticks out.
Measure the tote yourself, with the lid on and latched, across the widest points. That is the number the calculator needs.
What sticks out, and which direction it matters in
Lid overhang adds to width and depth. A snap-on lid typically overlaps the rim on all four sides.
Latches add to width or depth depending on which faces they are on, and they are usually the single widest point on a latching tote.
Carry handles add to width when they fold flat against the ends, and add to height when they fold up over the lid. A handle that folds up is the most common cause of a tote that fits the shelf but will not slide back out.
Moulded lips and stacking rims add to height, because a tote designed to stack sits slightly proud of its own lid.
Wheels change the height, not the footprint
Wheeled totes are measured to the bottom of the wheel, not the bottom of the body. Castors commonly add a noticeable amount of height while leaving width and depth close to unchanged.
A wheeled tote on a shelf is usually the wrong tool — the wheels raise it and cannot be used. If a wheeled tote is what you have, measure to the wheel bottom and expect the height to be the binding constraint.
Check your own measurements
Check your measured tote against your shelf — the calculator runs entirely in your browser and stores nothing.