Rear number plate size

[AndyPembs182]

The rear number plate looks a little on the small size on my 54 plate 182: should it be a non-standard size? My friend’s 172 seems to have a slightly enlarged one which fills the space more fully. Can anyone help?

 

[cat171]

Gotta pic ? As standard (lIke all UK plates) the front and back should be the same size.

 

[Crayola]

Standard size is 520x111mm