Yet Another Tip Calculator

User Guide

Sales Tax

Preferences related to sales tax are specified on the Settings view, which is accessed from the About view or by tapping in the subtotal area on the main calculator view. There are three preferences related to sales tax. Sales Tax % is the sales tax rate charged in your location. Tip on Pre-Tax and Sales Tax Rounding mode are two additional settings that control how YATC uses the sales tax percentage.

When Tip on Pre-Tax is ON, YATC will calculate the pre-tax amount from the entered post-tax subtotal and sales tax percentage. The Exact tip calculation will then determine the tip from the pre-tax subtotal.

If Tip on Pre-Tax is OFF, then the Exact tip calculation will determine the tip from the post-tax subtotal as entered. All other tax calculation methods are derived from the Exact tip calculation results.

The tip transaction summary email will include sales tax information, including the calculated pre-tax subtotal, only when Tip on Pre-Tax is ON. Similarly, the main calculator view will display the entered sales tax percentage in the upper right of the subtotal area only when Tip on Pre-Tax is ON.

Tip on Pre-Tax is Off: The upper right corner of the subtotal display is empty

Tip on Pre-Tax is On: Sales tax is displayed in the upper right corner of the subtotal display

Sales Tax Rounding mode allows you to choose the rounding mode for sales tax in your location. The laws concerning rounding of sales tax vary by region; for example, each U.S. state has different rules governing how sales tax should be rounded. It is beyond the scope of this application to track the different sales tax laws for each state, province, and country. Therefore, the calculated pre-tax amount may differ by a very small amount, usually by no more than $0.01 (or 1/100th of your native currency), from the pre-tax amount shown on your receipt. To achieve greater accuracy when calculating the pre-tax amount, you can specify how sales tax is rounded in your location:

Traditional: For this rounding mode, the sales tax calculation was carried to the third decimal place and rounded to a whole cent. If the third decimal place is a number greater than or equal to five, then the sales tax was rounded up. The following examples demonstrate the expected behavior for this rounding mode:
- 5.235 rounds up to 5.24.
- 0.357 rounds up to 0.36.
- 6.924 rounds down to 6.92.
- 8.240 rounds down to 8.24.
Up: For this rounding mode, the sales tax calculation was carried to the third decimal place and rounded up to the next cent if the third decimal place was greater than or equal to one. The following examples demonstrate the expected behavior for this rounding mode:
- 2.131 rounds up to 2.14.
- 9.291 rounds up to 9.30.
- 8.240 rounds down to 8.24.

While these rounding modes will cover many regions, they are not perfectly suited for states such as Florida, which use a bracket system for calculating sales tax. The app could have been designed to allow you to enter the exact tax amount, but doing so would clutter the interface and defeat the intended simplicity.

Last updated: Tuesday February 23, 2010