In short: every calculator uses a stated formula or an official figure, names its sources, is tested against worked examples before it goes live, and shows the date its content last changed. Ads never affect a result, and nobody can pay to change a tool.
1. Who Is Responsible
CalculatorsHub.us is owned and operated by 24London Invest Ltd, a company registered in England and Wales under company number 13183054. The company is responsible for everything published on the site, including the calculators, the explanations around them and this policy.
2. What We Publish
We publish free calculators, converters and small tools, together with short explanations: the formula a tool uses, worked examples, reference tables and answers to common questions. The site gives general information. It does not give personal financial, tax, medical or legal advice; the Disclaimer explains the limits of every estimate.
3. How We Choose Sources
We go to the organisation that sets or measures a figure, not to another website that repeats it. The sources we use most are:
- Tax and pay: the IRS, the Social Security Administration and state tax agencies
- Health insurance and benefits: CMS (Medicare) and the SSA
- Housing and prices: FHFA, Freddie Mac, the Bureau of Economic Analysis, the Bureau of Labor Statistics and the Census Bureau
- Health: the CDC, NIH, the USDA Dietary Guidelines and the WHO, plus the published research behind named formulas such as Mifflin-St Jeor or Widmark
- Units and science: NIST, NASA and the European Central Bank for exchange rates
Each tool page ends with a sources note naming where its figures come from. When a number is a rule of thumb or a population average rather than an exact figure, the page says so. We do not publish statistics we cannot trace to a source.
4. How Calculators Are Tested
Before a calculator goes live, and again after any change to it, we check its results against worked examples: the examples published by the source where they exist (for instance IRS tables), and hand calculations where they do not. We test ordinary inputs and edge cases such as zero, very large values and the limits of each bracket or range, on desktop and on phone screens. The formula a tool uses is explained on its page, so you can check the math yourself.
5. Keeping Figures Current
Many figures change on a yearly cycle. The IRS usually publishes next year's tax brackets and limits in the fall, the SSA announces the cost of living adjustment in October, and CMS and FHFA publish Medicare costs and loan limits late in the year. We update the affected tools when those figures are published, and whenever a law or agency changes a figure during the year.
Each tool page shows a Last updated date, often with a short note of what was checked. The date changes only when the content of the page actually changes, and it matches the date given to search engines. We do not re-date a page just to make it look fresh.
6. Corrections
If you think a result or a statement is wrong, email hello@calculatorshub.us with the page address, what you entered and what you expected. We check every report against the source. When an error is confirmed, we fix it, re-test the tool and update the page date; where the mistake could have affected your result, the update note says what changed.
7. How We Write
We answer the question first and explain after, in plain English. We avoid hype, invented numbers and claims we cannot support. Pages about money and health describe what a formula can and cannot tell you, and point to the official source or a professional for decisions that matter.
8. Use of Software and AI
We use software tools, including AI writing and coding assistants, to help draft text, write code and run checks across the site. They do not decide what we publish. Figures are checked against the named official source, and calculators are tested as described above, before a page goes live. The company named in section 1 is responsible for every page, however it was produced.
9. Advertising and Independence
The site is paid for by advertising. Ads appear only in clearly labeled slots, never inside a calculator, and the homepage has none. Until Google AdSense approves the site, the slots show ads for other websites run by the same company (LegalCost.us, discount5.us and favorit5.us), labeled Our network.
Advertisers have no say over our content. We do not accept payment to add, rank, word or change a calculator or its results, and we do not publish paid reviews. If we ever use affiliate links, they will be labeled on the page where they appear.
10. Contact
Questions about this policy, suggestions for a new tool or a correction: hello@calculatorshub.us, or use our contact page.
24London Invest Ltd, company number 13183054, registered in England and Wales. Registered office: Flat 9 Kintyre House, Explorer Drive, Watford, WD18 6GR, United Kingdom.