Calculate restaurant tips on the pre-tax subtotal. Factor in tax, choose your tip percentage, and split the bill between your party.
It is customary to calculate the tip on the pre-tax subtotal, as the tax goes to the government and not the server. This calculator uses the pre-tax amount for accuracy.
Many restaurants add an automatic 18-20% gratuity for parties of 6 or more. Check your bill for an included gratuity before adding an additional tip. If service was exceptional, you can add extra.
Consider leaving at least 10% for poor service in the US, as servers rely on tips for their income. If the issue was with the kitchen rather than the server, tip normally and speak with a manager about the food.