About Holdentree
One person.
No investors.
Just the math
Holdentree started as spreadsheets built for one person's own decisions — a mortgage refinance, an RSU sale, a Roth conversion — because the number had to be exact and nothing off-the-shelf matched the situation. It has grown since. The reason for building the next one hasn't changed.
Browse the calculators- No ads
- No sponsors
- No affiliate links
- Nothing sent to a server
- No paid tier
- One person, no company
Why it exists
No shareholders to please
Every tool here started as one I built for myself first — for a tax bracket, a mortgage decision, a Roth conversion — because the number had to be exact and nothing off-the-shelf matched the situation.
No ads, no sponsors, no affiliate links
Nothing on this site is placed because someone paid for the slot, and no company decides which calculator gets built next. The only funding is direct: readers who choose to support the site because a tool saved them something.
Nothing you type leaves your browser
Every calculator runs entirely client-side. There is no account and no server that ever sees your income, your balances, or your debts — only your own browser's local storage, which exists to save your inputs for next time and clears with one click.
Figures are sourced, not guessed
Every dated calculator — tax brackets, withholding rates, Medicare premiums, Social Security figures — is built from the primary government publication, not a summary blog post. The current tools use published 2026 figures, and a calculator that depends on a specific year says so on its card.
Reviewed on a schedule, not left to rot
Dated figures get re-verified against that year's primary source before rolling forward. If you spot one that looks wrong, say so — reader reports are how most of them have ever been caught.
Calculators, not a sales floor
The output is for you, not a salesperson
A calculator built by a bank, a lender, or a comparison site has a reason to nudge the number its way. This one doesn't sell anything, so nothing here benefits from the answer coming out one direction over another.
No lead capture
There's no "get your rate" button quietly handing your inputs to a lender or broker. What you calculate never leaves this tab, let alone gets packaged up and sold as a lead.
No recommended providers
No sponsored lender, insurer, or brokerage gets a name on any page, and no calculator is tuned to make one company's product look better than a competitor's.
The output is yours
You get a number and a clean export, not a quote request. Nothing here is built to guide you toward buying a specific product — only to help you understand your own numbers.
No urgency, no funnel
No countdown timer, no "rates are about to change," no follow-up email. There's nothing here trying to get you to act before you're ready.
Not personalized advice, either
Not a financial advisor, not a CPA, and not a substitute for either. Every result is an estimate for planning against your own numbers, built from public rules applied consistently — not personalized advice, and not a recommendation to buy, sell, or choose any specific product. For anything with real money riding on the answer, especially near a threshold or a filing deadline, that's what a professional is for.
That's the whole operation — one person, a folder of calculators, and nothing for sale.
If a figure looks wrong, say so. If a calculator is missing, ask for it. Everything on this site exists because somebody needed it, starting with me.