We built PennyCalc because the existing calculators didn't work for people like us.
Three founders working across industries and locations, but facing the same challenges. We all built financial models in Excel and Google Sheets for ourselves - mortgage comparison spreadsheets, hotel/airline point optimization, 401(k) projections, RSU tax estimators - and passing them around in our group chat whenever someone had a big financial decision coming up.
Josh was building financial models at a private equity firm, but couldn't find an online calculator that handled PMI cancellation at 78% LTV correctly (he was buying his first home in Manhattan). Jessie had a background in management consulting and was building her own Roth conversion analysis in Google Sheets because every online tool assumed she was a median earner. Michael, a consultant turned builder, had rebuilt the same 401(k) optimizer in Excel four times because colleagues kept asking for a copy.
At some point, we looked at the collection of spreadsheets we had developed and realized: these are better than what's widely available. Not because we're smarter, but because we actually use them, test them, and refine them. We built for our own edge cases and it turns out those edge cases are pretty common among people who earn well and have complicated financial lives.
So we turned the chat-shared spreadsheets into a website.
Who this is for
PennyCalc is built for people whose financial lives have real complexity. Jumbo loans. AMT exposure. Backdoor Roth strategies layered on top of RSU vesting schedules. Capital gains planning across multiple holding periods. SALT cap scenarios.
Most financial content online is written for someone asking "what is a 401(k)?" That's fine, but it's not you (nor is it us). You know what a 401(k) is, but you want to know how to maximize your returns. What happens to your tax bracket if you max it out, do a mega backdoor Roth, and your spouse's RSUs vest in the same year. Our calculators handle that because we've personally dealt with every one of those scenarios.
What we actually do differently
The math is visible. Every calculator shows you how it gets its numbers. Amortization schedules, bracket breakdowns, year-by-year projections. No "talk to an advisor" wall. No black boxes.
The assumptions are stated and overridable. When we default to a 1.1% property tax rate or $1,200/year homeowner's insurance, we tell you and let you change it. Your county's rate is probably different and you should use yours.
The examples come from real decisions. When we write about shopping for a jumbo loan and finding that credit union rates beat the big banks, that happened. When we compare PMI elimination strategies at 78% vs. 80% LTV, that's an analysis one of us ran for an actual purchase. The insights on this site come from decisions we made with our own money.
We don't give advice (and that's not our job). We build tools that we use ourselves and share them with you. Run your scenarios, draw your own conclusions, and talk to a professional if you need guidance specific to your situation.
The team
How PennyCalc makes money
We're transparent about this: PennyCalc earns revenue through display ads and affiliate partnerships. When you see a "Compare Rates" button or a link to a financial product, clicking it may earn us a commission.
This never affects the calculators or the content. The math doesn't change based on who's advertising. We chose this model because it means the tools are free - no signup, no email capture, no paywall.
Get in touch
Found a bug in a calculator? Have a scenario our tools don't cover? We want to hear about it.
Email: [email protected]
Every error report gets investigated. Getting the math right is the whole point.