About Calculator Dad
I'm Michael Phillips. I build the calculators here, and I check every number on them myself.
Numbers came first
I was the kid who liked long division. Maths was the subject I never had to be made to do, and it stayed that way through school — it was the one place where an answer was either right or it wasn't, and you could always go back and find out which.
That's still roughly how I think. Most arguments are opinion. Arithmetic isn't.
Economics, then markets
I studied economics for three years. It taught me how to read a dataset and, more usefully, how often a confident-looking number turns out to rest on an assumption nobody wrote down.
Now I trade for a living. Day trading is a blunt teacher on exactly that point: if you take a figure on trust and it's wrong, you don't get a mark deducted, you lose money the same afternoon. You learn quickly to go and look at the source yourself.
Why I build calculators
Because it's fun. That's the honest answer.
I like taking something fiddly — a tax bracket, a loan schedule, a conversion nobody can ever remember — and turning it into a box where you type a number and get the right one back. Small problem, clean solution, done. There are thousands of them and I enjoy every one.
Calculator Dad is where they go. What the site is for, and who I'm building it for, is on our mission page.
How I work
- Primary sources. Rates come from the state's own revenue department — the withholding guide, the rate schedule, or the bill text. Not from another website.
- Every page says when it was checked, and links to the exact document it was checked against.
- Re-checked on a schedule. Weekly through the March-to-June legislative season when states actually change things, monthly the rest of the year.
- The workings are printed. If a calculator tells you a number, it should show you how it got there.
- Corrections get published, not quietly edited. If I've had something wrong, the page says so.
Found a mistake?
Tell me. I would much rather fix a wrong figure than defend one. The fastest route is @phillips9320, or the corrections page.
If you found an error in a tax figure, I'll check it against the state and, if you're right, correct it and note the change on the page with the date.