I never know how much to tip. Which is to say, each time I enjoy a nice meal served by a waiter/waitress at a restaurant, the meal’s end finds me silently calculating - and worrying about - the tip. How much is too much? Is my plan too little? (Do you still give the pizza man just $2.00?)
My personal hack? The sales tax in Houston, where I most often eat out, is 8.25%. I simply double the tax on the check and guesstimate from there. A little less for average service, a little more for great service. Of course, this handy-dandy method fails whenever I travel, the check is manually divided among multiple parties, or whenever there’s alcohol involved because I remain unclear about the mystery algorithm to wine purchases that completely throws everything out of whack.
Who needs that worry at the end of a good meal? If the reason restaurants give you a mint as you walk out the door so your last memory of the place isn’t of a heavy meal but a refreshing mint, wouldn’t it stand to reason that restaurants want to be good stewards of their customer experience right before your departure as well?
For one of the best examples of this stewardship, I submit Houston’s Restaurants’ Gratuity Quick Guides.

Houston's Restaurants Helpful Gratuity Quick Guide
Now, I know this example is a little fuzzy (the place was a little dim when I took this picture with my iphone), so here’s a recap. My bill was $37.08. Houston’s figured my tipping options: @15% = $5.54; @18% = $6.67; and @20% = $7.42. What’s particularly interesting here is that they gave me a list of acceptible options with over $2 in range. That’s not chump change when we’re talking about the lower end starting out at $5.54.
Of course, this helpfulness also benefits and incentivizes the waitstaff. One assumes Houston’s wants their staff reasonably compensated, and the gratuity guide helps along both those of us who are a bit clueless with math and provides a bit of social proof for the tightwads among us. Similarly, waitstaff know that there’s a tipping range and that their thoughtful, polite, and timely service has a greater chance of being rewarded at Houston’s versus a gratuity guideless alternative.
Another great example of an easy to implement, simple, thoughtful solution to an everyday problem. Everyday. Usability!