Terms of Service
Effective September 25, 2026
Harbors Calculators is run by Usman Ali and is a set of free calculators and explanations. Using the site means accepting what is on this page. It is short because the site does not ask much of you: there is nothing to sign up for, nothing to pay, and nothing to agree to beyond the sense below.
What the results are
Estimates, worked out from the numbers you type and the assumptions each page states. They are not financial, tax, legal or medical advice, and no relationship with a professional is created by using them. A calculator does not know your credit file, your local fees, your lender's charges or your medical history, and those are exactly what move a real quote away from an estimate.
We take accuracy seriously. Formulas come from primary sources, each carries automated tests, and the downloads are checked by opening the files and reading them back. Even so, the site is provided as it is, with no warranty that it is free of errors or fit for any particular purpose. Decisions you make from a result are yours, and to the extent the law allows, we are not liable for them. Check anything that matters before acting on it.
The disclaimer sets that out in full, and the methodology explains how the numbers are produced and what they cannot cover.
What you may do
Use the calculators for anything you like, personal or commercial. Run a mortgage for yourself, price a car for a client, put a schedule in front of your accountant. The files you download are yours: print them, email them, attach them to a proposal, keep them. None of that needs our permission and none of it costs anything.
What you may not do
- Scrape the site at scale, or hit it with automated traffic that degrades it for others.
- Republish our explanations, worked examples or page text as your own.
- Take the code or the design apart to stand up a copy of this site.
The line is between using a calculator and taking the site. Working out a hundred scenarios is using it. Pulling every page down to rebuild them elsewhere is not.
What belongs to whom
The formulas are public knowledge and always were: compound interest belongs to mathematics, and the CDC's BMI bands belong to the CDC. Nobody owns those and we do not claim to.
What is ours is the work around them: the explanations, the worked examples, the page design and the code that runs the calculators. That stays ours. The name Harbors Calculators and our logo are ours as well, so please do not use them in a way that suggests we made something we did not or endorsed something we have not seen.
Availability
There is no uptime promise here. The site may go down, and it may change: a calculator can be corrected, reworked or withdrawn, and a feature you rely on may not be here next month. If a calculation changes, the page's date changes with it, so you can tell whether the figure you saved still matches what the tool returns today.
Other services and links
The site uses third-party services to run, such as hosting and, once it is live, advertising. It also links out to regulators, agencies and published research so you can check our claims at the source. Those services and sites have their own terms, we do not control what they publish next, and a link is not an endorsement of everything else on the other end of it. How data is handled is in the privacy policy.
Changes to these terms
These terms can change, and the effective date at the top changes with them. Using the site after that counts as accepting the version then on the page. There is no account to notify, so the date is the honest signal to watch.
Governing law
The site is operated from Pakistan, and these terms are governed by the laws of Pakistan. Nothing here takes away rights that the law where you live gives you and does not allow to be signed away.
Questions
Email is still being set up. The contact page says where things stand in the meantime.