Oh dear, depends whether you're talking houseplant or a fruiting fig for outside. which do you mean?

hi bamboo,i mean a house plant

Well the smallest one would be Ficus pumila minima, or Ficus Sunny, but you'd better Google them, they may not be at all what you've got in mind. There's one called Ficus buxifolia which is a sort of dwarf shrub - comes in plain green or variegated with yellow.

thanks bamboo very useful info ,i shall look on google as you say