About Us

Last updated: 16 September 2026

Stack Frame is a small collection of free online calculators that I built for myself, and then left online in case anyone else finds them useful. There is no company behind it, no team, and no signup: you open a calculator, type your numbers, and get an answer.

Who runs this site

I’m Elliot Vance. I have an ordinary full-time office job that has nothing to do with finance, law, medicine or engineering, and building small web tools is a hobby. I write them with AI assistants, then sit down with a handheld calculator and check the output against a worked-by-hand example before anything goes live. This is a hobbyist’s toolbox, not a consultancy.

I am not an accountant, financial adviser, tax preparer, lawyer, insurance agent, engineer, appraiser or healthcare professional. I hold no licence in any of those fields and I do not work in them. If a decision matters enough to affect your money, your business or your health, treat a number from here as a starting point and confirm it with a licensed professional or the official source.

Why it exists

It started with two recurring annoyances:

  • At work — freight quotes that needed a freight class, a pallet density and a landed cost before I could answer anyone.
  • At home — the usual personal-finance questions: what a loan repayment really costs, what a tax figure works out to, which of two options is cheaper.

I kept rebuilding the same spreadsheet, so I started turning each calculation into a one-page tool. Colleagues and friends asked for copies, and the pages stayed online. Everything here is something I have personally needed at least once — which is also why the mix looks odd at first glance (shipping costs next to dog food portions).

What is actually on the site

Roughly 270 free calculators, grouped into six areas:

Most of the English tools also have a Japanese version under /ja/.

How the tools are made and checked

  • Formulas come from published sources — standards, government and regulator publications, textbooks, or the official documentation of whatever is being measured. Where a result depends on a convention (a tax year, a freight classification rule, an interest convention), the assumption is stated on the tool page.
  • Each calculator is tested against a hand-worked example before it is published, and the example is kept so a later change can be re-checked.
  • Reference values change. Tax brackets, contribution limits and fuel indices move over time. I update them when I notice a change — if you spot a stale one, tell me and I will fix it.
  • Your inputs stay yours. The calculators run in your browser, I don’t store your numbers, and I don’t verify them.

If something is wrong

Email [email protected] with the tool name and what looks off. I will re-derive the formula, fix the page, and add a note saying what changed and when. Corrections are the main way this site gets better, and they are the reason I would rather publish a plain tool than a confident-sounding article.

What this site is not

It is not professional advice and it is not a substitute for it — see the full Disclaimer. It is not a quote, an invoice, a tax filing or a valuation. And it is not a data service: please treat every result as an estimate to check rather than a fact to act on.

Contact

Email: [email protected]. I read everything and usually reply within a couple of days. There is also a contact page.