Although both words mean can be eaten, there is a slight difference between them. Edible refers to waht may normally be eaten whereas eatable refers to thetaste or flavor of the food. For this reason, something which is edible may sometimes be uneatable.

The prison food was edible. 

Mushrooms are eatable.

Quoted from Wen Shin Use the Right Words, by Ronald Chiu


I really believe the examples are switched there.

- Some mushrooms are edible (they can be eaten with no harm to your health), but most of them are not edible (they will kill you or give you a stomach ache). Edible is a universal quality applied to that thing.

- The prison food was eatable (because not only it was prepared with edibles, but the dishes were done well, cooked with care). Eatable is a specific quality applied to that food in front of you and the current "state" of it.

That way, tequila worms are edible (you can eat them if you want), but are not eatable (you don't wanna do it...).


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In British English both are possible

Eatable generally means 'good enough (in flavour, wuality, etc) to eat', while edible means that it is not poisonous.

However many people use just one of them for both meanings. Some use eatable, others edible.

It is difficult to know whether a person who says 'The dinner she served up was inedible' is using what some would say was the incorrect word, or is jokingly using the correct word to suggest that to eat it would prove fatal.