Use percent-of calculations and know whether the percentage is added or subtracted.
Quick answer
The three workflows use percent-of, ratio-to-percent and relative-change formulas.
Discount
The three workflows use percent-of, ratio-to-percent and relative-change formulas. In this context, discount matters because the output should match the task rather than simply produce a file or string. Review the result against the original input and keep an untouched copy when the workflow changes a file.
Tax
The three workflows use percent-of, ratio-to-percent and relative-change formulas. In this context, tax matters because the output should match the task rather than simply produce a file or string. Review the result against the original input and keep an untouched copy when the workflow changes a file.
Subtotal
The three workflows use percent-of, ratio-to-percent and relative-change formulas. In this context, subtotal matters because the output should match the task rather than simply produce a file or string. Review the result against the original input and keep an untouched copy when the workflow changes a file.
Practical example
Use the matching Get Tools Lab Percentage Calculator tool with a small, non-sensitive example first. Confirm the expected result before using a larger or important input.
Privacy and limitations
Processing behavior depends on the tool. Priority browser-local tools identify that behavior on the tool page. A local browser workflow reduces server upload exposure, but it does not remove the need to protect the source file, device and downloaded result.
Related workflow
Open Percentage Calculator. You can also use the related comparison, glossary and topic pages to understand the format and trade-offs.