I use Tasty's calculator
to determine the amount of priming sugar when bottling. When priming a keg, I use 1/4 of a cup of table sugar
for English ales (less carbonated), or 1/3 of table sugar for American and Belgian ales (more carbonated). Sometimes, when I have too much beer to rack it to a keg, I bottle just a few bottles and use single priming drops from Coopers.