"Contact sales for complete package dimensions"

When the alternative to signing an NDA is "calipers".

Macronix offers an SPI flash in an 8-ball WLCSP whose width and length are considered so sensitive they are omitted from public datasheet:

GigaDevice lineup includes a similar SPI flash in a more complex 82-ball WLCSP where the ball coordinates are specified unambiguously, but to find out the overall width and length you have to scale the drawing or email the salesperson:

(I'm not sure why they call it a 3-2-3 ball WLCSP and do not include the ball count in the documentation.)