I prefer taking 10% and doubling it for a 20% tip.
Take the total, moved the decimal one digit to the left, double it and round to the nearest dollar. I round up at the beginning and end as well which is either close enough or a dollar high if the change is small enough.
I either do this, or mentally divide by 5 (how many 5s make this number?), only caring about the closest whole number - I prefer to tip in whole dollar amounts to make the math easy.
Eg. $39.53 is about $40, 40 is 8 fives, so tip $8
If the service wasn’t great I round down instead of up.
I prefer taking 10% and doubling it for a 20% tip.
Take the total, moved the decimal one digit to the left, double it and round to the nearest dollar. I round up at the beginning and end as well which is either close enough or a dollar high if the change is small enough.
$138.72 > 139 > 13.9 > 27.8 > $28
Close enough!
I either do this, or mentally divide by 5 (how many 5s make this number?), only caring about the closest whole number - I prefer to tip in whole dollar amounts to make the math easy.
Eg. $39.53 is about $40, 40 is 8 fives, so tip $8
If the service wasn’t great I round down instead of up.
I multiply the tip by 5 to double check my math which is how I know it comes out as a dolllar higher sometimes.
28x5=140