You won’t go far wrong if you add two teaspoonsful of salt for every litre of water, bearing in mind that you should use at least one litre of water for every 100 g of pasta. When it comes to salt, you need to be just as careful not to overdo it as not to underdo it, and you should add salt once the water has boiled, or else it will take longer to boil, since salt water has a higher boiling point.
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How to calculate the right amount of salt for pasta
1 March 2016