The Netherlands' biggest cannabis-selling coffee shop has been fined almost $15 million for breaching the country's relatively lax drug laws.

A Dutch court fined the owner of Amsterdam's Checkpoint cafe after police seized more than 200 kilograms of cannabis on the premises.

Licensed cafes are only allowed to stock half a kilogram of cannabis under Netherlands law, a limit often flouted.

The Dutch court said the $14.7 million fine would have been higher had it not been for a lax approach to the sales and use of soft drugs.

It said authorities had known for years about the thousands of people visiting Checkpoint, but did not act.

Sentences for other workers and suppliers ranged from warnings to those who rolled joints to six-week jail terms.