Adding the word metric to your search is an easy way to filter to only include recipes which give metric quantities.
e.g.
​vegetarian aubergine recipes (658 recipes)
vs
​vegetarian aubergine recipes metric (296 results)

In the future, ckbk will also offer the ability to convert a recipe to your prefered units. For now an online units converter such as this one can be used to convert measurements as needed.
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