POS tip checker

Suggested Tip Checker

Check whether a restaurant or checkout screen suggested tip was based on the bill before tax, after tax, before discount, or after discount.

This tool gives a close estimate only. It does not judge the business or replace the receipt details. Ask the business if a charge or tip screen is unclear.

Check a Tip Tip before or after tax

Tip basis check

Find the closest tip basis

Enter the receipt numbers shown on the screen. The result updates as you type.

Closest match After-tax total

Difference$0.00

Effective pre-tax tip21.6%

Effective after-tax tip20.0%

After-discount base$50.00

Direct answer

Why suggested tips can be confusing

A payment screen may calculate a suggested tip on the pre-tax subtotal, the after-tax total, the amount before a discount, or the amount after a discount. A small change in the base can change the tip amount.

Formula

How this checker works

Expected tip = possible base × displayed tip percent
Difference = suggested tip amount − expected tip
Closest match = the possible base with the smallest dollar difference

Examples

Common suggested tip examples

These examples show why two screens can show different 20% tip amounts.

Post-tax suggestion

$50 subtotal, $4 tax, and a suggested 20% tip of $10.80 likely means the tip was calculated on $54 after tax.

Pre-tax suggestion

$50 subtotal, $4 tax, and a suggested 20% tip of $10.00 likely means the tip was calculated on the pre-tax subtotal.

Pre-discount suggestion

If a coupon lowers the bill but the suggested tip still matches the original subtotal, the payment screen may be using the pre-discount amount.

Common screen-tip mistakes

Assuming the suggested tip is always based on the pre-tax subtotal.
Not noticing that a discount changed the final bill.
Adding an extra tip when automatic gratuity is already included.
Comparing a rounded tip amount to an exact percentage.

Privacy note

This checker runs in your browser. It does not require sign-in and does not need a server database to compare your receipt numbers.

Suggested tip checker FAQs

What does the suggested tip checker do?

It compares the tip amount shown on a receipt or payment screen with common tip bases, such as subtotal before tax, subtotal after discount, and subtotal plus tax. It then shows which basis is closest.

Why can suggested tips look higher than expected?

A suggested tip can look higher when it is calculated after tax, before a discount, or on a total that includes fees. The checker helps you compare those possibilities.

Should I tip before tax or after tax?

Many people calculate restaurant tips before tax because sales tax is not part of the service price. Tipping after tax is simpler and slightly more generous.

Can this tool prove a business did something wrong?

No. The tool is only a personal estimate. Receipt systems, discounts, service charges, and local rules can vary, so ask the business if the wording is unclear.

Does USTipCalc store my receipt details?

No. This calculator runs in your browser and does not require an account or server database to compare receipt details.