5 ms·

It is so very true, though. Over the years I've had to teach my "trick" for figuring out tips without a calculator to pretty much all of my friends (the spiel:

It is so very true, though. Over the years I've had to teach my "trick" for figuring out tips without a calculator to pretty much all of my friends (the spiel: 'move the decimal one place to the left; double that number'). I was always surprised by how magical it appeared to them :|

dionidium 13y ago
It's painful to watch an otherwise successful person whip out a calculator to make sure they don't accidentally give their server an extra 30 cents on an ~$18 lunch bill. Just round up and move on with your life. Everybody wins.
- tzs 13y ago
  Tip calculators all go the wrong way (well, all the ones I've seen do). Suppose I order a pizza and it comes to 16.12. A typical tip calculator will tell me that with a 15% tip, this would be 18.54, and with a 20% tip it would be 19.34. I don't want to screw around with that .54 or .34. I want to give the delivery person an integral number of dollars. Probably hand him a $20, and tell him how many dollar bills to give me back. I made a tip calculator Dashboard widget to calculate tips from that perspective. With this widget, I enter 16.12, and it gives me a little table that looks like this: $17.... 5.5% $18....11.7% $19....18% $20....24.2% $21....30.5% I can glance at that, and see that $19 or $20 for combined $16.12 pizza plus tip are reasonable options. If it were summer, I'd probably go for $19, especially if I could do that without breaking a $20. If it were winter, I'd probably just go with a $20 bill and no change, to get the transaction over with as quickly as possible so I could close the door and stop losing my precious heat.
patio11 13y ago
I watched an American gentleman helpfully suggest that to a Distinguished Professor of Statistics from a top 10 university in Japan. It took me 10 minutes in the car ride home to assure him that it was not an insult to his intelligence.
skywhopper 13y ago
Even easier (and better for your karma and the server's budget): round the bill up to the next 10 dollar increment, then do this trick (and add a buck). Also, never use the pre-tax amount, cheapskates!
- bluedevil2k 13y ago
  You're supposed to use the pre-tax amount, and doing what is normal, paying 15% of the pre-tax amount, doesn't make you a cheapskate, it makes you normal. You don't get bonus points for paying extra money to someone you'll likely never see again.
  - dionidium 13y ago
    The difference between 15% and 20% on a $15 bill is 75 cents. The difference between pre- and post-tax is even smaller. You might not get bonus points for ignoring that, but you'll definitely lose points (in my eyes, at least) for fretting about such a small amount of money.
    - freehunter 13y ago
      Anyone loses points (in my eyes) for tipping an exact amount regardless of the quality of service. It's a tip, it's supposed to reflect how well you were treated. If you do 18 or 20% no matter what, you're missing the point of tipping. If I'm eating spicy food and my glass is empty for the entire duration of my meal because the server is not paying attention, you're lucky to get a tip at all. I've left 50% tips, I've left no tip, and I've rounded $9.99 to $10 and called that a tip. Anyone working in a restaurant expecting a tip for bare minimum service has my pity, but not my money. You get my money by doing a good job.
      - dionidium 13y ago
        It's a tip, it's supposed to reflect how well you were treated. That may be how the practice started, but that's no longer how it works. I mean, you can clearly tip however little or much you'd like, but, culturally, the tip is nothing more than a formality. And like any formality, you're free to ignore it, but you should be aware that that's what you're doing.
zackbrown 13y ago
I've taken to tipping 18%, and the process I use to calculate that mentally starts with what you mentioned, but with one more step: Divide by 10 for 10%; double that number for 20%. Take 10% away from that number to get 18%. E.g. 100 check move the decimal => 10 double that => 20 move the decimal => 2 subtract previous value from the one before (thus 90% of 20%, or 18%) => 18 This feels like a good mental math exercise to me on a 4- or 5-digit number since it requires a couple of values to be remembered while you're calculating. Gotta stay sharp!
- deleted 13y ago
  [deleted]
- tzs 13y ago
  Note that 1°C = 1.8°F, so your techniques for 18% tips can be adapted to C => F conversion (T x 1.8 + 32 to go from C to F).
bluedevil2k 13y ago
Here in Texas, with the tax rate of 8.25%, simplest method is to simply double the tax rate to get your tip.
oinksoft 13y ago
Do you eat out enough that tipping is a significant expense? I just estimate 20% and round to the next dollar, $0.40 isn't going to bleed me dry and most servers make crap anyway.
- jparishy 13y ago
  Same, the rounding step was just implied. My point was that for a lot of people "just estimating 20%" in their head is wizardry

dionidium 13y ago

It's painful to watch an otherwise successful person whip out a calculator to make sure they don't accidentally give their server an extra 30 cents on an ~$18 lunch bill. Just round up and move on with your life. Everybody wins.

tzs 13y ago
Tip calculators all go the wrong way (well, all the ones I've seen do). Suppose I order a pizza and it comes to 16.12. A typical tip calculator will tell me that with a 15% tip, this would be 18.54, and with a 20% tip it would be 19.34. I don't want to screw around with that .54 or .34. I want to give the delivery person an integral number of dollars. Probably hand him a $20, and tell him how many dollar bills to give me back. I made a tip calculator Dashboard widget to calculate tips from that perspective. With this widget, I enter 16.12, and it gives me a little table that looks like this: $17.... 5.5% $18....11.7% $19....18% $20....24.2% $21....30.5% I can glance at that, and see that $19 or $20 for combined $16.12 pizza plus tip are reasonable options. If it were summer, I'd probably go for $19, especially if I could do that without breaking a $20. If it were winter, I'd probably just go with a $20 bill and no change, to get the transaction over with as quickly as possible so I could close the door and stop losing my precious heat.

patio11 13y ago

I watched an American gentleman helpfully suggest that to a Distinguished Professor of Statistics from a top 10 university in Japan. It took me 10 minutes in the car ride home to assure him that it was not an insult to his intelligence.

skywhopper 13y ago

Even easier (and better for your karma and the server's budget): round the bill up to the next 10 dollar increment, then do this trick (and add a buck). Also, never use the pre-tax amount, cheapskates!

bluedevil2k 13y ago
You're supposed to use the pre-tax amount, and doing what is normal, paying 15% of the pre-tax amount, doesn't make you a cheapskate, it makes you normal. You don't get bonus points for paying extra money to someone you'll likely never see again.
- dionidium 13y ago
  The difference between 15% and 20% on a $15 bill is 75 cents. The difference between pre- and post-tax is even smaller. You might not get bonus points for ignoring that, but you'll definitely lose points (in my eyes, at least) for fretting about such a small amount of money.
  - freehunter 13y ago
    Anyone loses points (in my eyes) for tipping an exact amount regardless of the quality of service. It's a tip, it's supposed to reflect how well you were treated. If you do 18 or 20% no matter what, you're missing the point of tipping. If I'm eating spicy food and my glass is empty for the entire duration of my meal because the server is not paying attention, you're lucky to get a tip at all. I've left 50% tips, I've left no tip, and I've rounded $9.99 to $10 and called that a tip. Anyone working in a restaurant expecting a tip for bare minimum service has my pity, but not my money. You get my money by doing a good job.
    - dionidium 13y ago
      It's a tip, it's supposed to reflect how well you were treated. That may be how the practice started, but that's no longer how it works. I mean, you can clearly tip however little or much you'd like, but, culturally, the tip is nothing more than a formality. And like any formality, you're free to ignore it, but you should be aware that that's what you're doing.

zackbrown 13y ago

I've taken to tipping 18%, and the process I use to calculate that mentally starts with what you mentioned, but with one more step: Divide by 10 for 10%; double that number for 20%. Take 10% away from that number to get 18%. E.g. 100 check move the decimal => 10 double that => 20 move the decimal => 2 subtract previous value from the one before (thus 90% of 20%, or 18%) => 18 This feels like a good mental math exercise to me on a 4- or 5-digit number since it requires a couple of values to be remembered while you're calculating. Gotta stay sharp!

deleted 13y ago
[deleted]
tzs 13y ago
Note that 1°C = 1.8°F, so your techniques for 18% tips can be adapted to C => F conversion (T x 1.8 + 32 to go from C to F).

bluedevil2k 13y ago

Here in Texas, with the tax rate of 8.25%, simplest method is to simply double the tax rate to get your tip.

oinksoft 13y ago

Do you eat out enough that tipping is a significant expense? I just estimate 20% and round to the next dollar, $0.40 isn't going to bleed me dry and most servers make crap anyway.

jparishy 13y ago
Same, the rounding step was just implied. My point was that for a lot of people "just estimating 20%" in their head is wizardry