Tipping at restaurants is second nature for many people, but figuring out the right amount can sometimes feel like a math test. That’s why TikTok user Alex Newnam decided to share a quick and easy hack to calculate the perfect tip every time—without using a calculator.
Her trick was simple:
- Move the decimal one place to the left to find 10% of the total.
- Double that amount to calculate a 20% tip instantly.
It seemed like a foolproof method, but not everyone was convinced.
@alex_newnam Taking y’all back to school ✏️🍴💰 #tiptrick #resturant #money #math #tip #dinner #check #bill
The Trick in Action
In her viral TikTok video, Alex demonstrated the technique using a $64.93 bill. She moved the decimal to the left, landing at $6.50, which represents 10% of the total. Doubling that gave her a $13 tip, making it a quick way to determine 20% without pulling out a calculator.
She proudly claimed that with this trick, people would “never need a calculator again” when figuring out how much to tip.
However, while the method itself does work, some sharp-eyed viewers pointed out one major flaw in her approach.
The Big Problem Viewers Spotted
Shortly after Alex shared her tipping trick, people flooded the comments with one key issue—she was calculating the tip based on the post-tax total instead of the pre-tax subtotal.
Here’s why that’s a problem:
- Sales tax varies by state and is not part of the service you’re tipping for.
- Tipping on the total means you’re also tipping on tax, which doesn’t go to the server.
- Standard tipping etiquette suggests calculating the tip on the subtotal—the cost of food and drinks before tax is added.
One user quickly called her out, writing:
“Don’t tip off the total, that includes tax. You tip off the subtotal.”
Another asked:
“Why would you tip on the tax??”
A third added:
“Nope! The tip should be calculated before tax is added in.”
While Alex’s trick is still a fast and useful way to estimate a tip, many agree it should be applied before tax is included.
The Great Tipping Debate
Beyond the math issue, Alex’s video also reignited the age-old tipping debate. While some people believe 20% is the standard tip, others think it’s too high.
Some comments reflected more traditional tipping habits:
- “20% is way too high. 15% used to be the standard!”
- “I tip 15% unless the service is outstanding, then I’ll do 20-25%.”
- “I tip based on service, not a set percentage.”
Meanwhile, others admitted they don’t tip at all:
- “I don’t tip.”
- “Leave no tip.”
- “Put a zero on the tip line.”
This reaction highlights how tipping culture varies between individuals, regions, and even generations.
So, Does the Trick Work?
Yes, Alex’s tip hack is useful, but it’s important to use the subtotal instead of the total to avoid tipping on tax. If you struggle with mental math at restaurants, this method is still a quick and easy way to calculate a 20% tip—just be sure to do it correctly.
At the end of the day, how much you tip is a personal choice, but understanding proper tipping
