Methodology and corrections
NewsLive calculators are meant to give you a number you can act on and a clear explanation of where it came from. This page explains how each one is built, how it is checked, and what to do if you find a mistake.
Where the formulas and figures come from
- Tax, retirement and benefit limits come from primary sources: IRS revenue procedures, notices and newsroom releases, the Social Security Administration, the U.S. Department of Labor and state agencies. Each calculator lists the exact documents it relies on, with links.
- Financial formulas such as compound interest, loan payments and present value use standard textbook formulas. Where a regulator publishes a reference calculator, such as the SEC’s Investor.gov tools, we check our results against it.
- Health and fitness estimates use published equations and name them on the page, along with their known limits.
How every calculator is tested
Before a calculator goes live, its formula is run against a set of worked test cases with answers computed independently, for example by hand or from the closed-form formula, rather than by the calculator’s own code. A calculator is published only when every case passes. If the code changes later, the publishing system blocks the page until the tests are run again and pass.
The example result shown when a page first loads is produced by the same tested code, so the numbers in the article and the calculator always agree.
Data years and “last checked” dates
Every calculator shows the date its figures were last checked and, where it matters, the tax or plan year it uses. When the IRS or another agency publishes new limits or brackets, affected calculators are updated and their dates change. We do not change the date on a page unless its content was actually reviewed.
Extra review for money, tax and health pages
Calculators that touch taxes, benefits, legal obligations or health are held as drafts until a person has reviewed the inputs, the results for typical cases and the explanatory text. Results are estimates for planning and education, not personal tax, legal, medical or investment advice.
Your numbers stay in your browser
Calculations run on your own device. The numbers you type are not sent to NewsLive. The Copy link to this result button puts your inputs in the page address so you can share or bookmark them; only people you send the link to will see them.
Corrections
If you think a calculator or article is wrong, email corrections@newslive.com with the page address and the inputs you used. We check every report. Confirmed errors are fixed, the page’s “last checked” date is updated, and significant corrections are noted on the page.
Using our calculators on your site
Each calculator page includes a free embed code. You may use it on any website as long as the credit link back to the calculator page stays in place. You may also cite our pages; each one shows a ready-made citation.