moneycrunchlab
25 private financial calculators — no sign-up, embeddable
MoneyCrunchLab is a collection of 25 free financial calculators covering mortgages, debt payoff, savings, and retirement. Every tool computes entirely in your browser — the numbers you type never leave it — with no sign-up, no tracking, and no ads inside the tools. Each calculator states its assumptions right next to the results and shows the losing side of a trade-off when there is one: the rent-vs-buy and 15-vs-30-year comparisons will happily tell you the "wrong" answer wins. The math is verified against closed-form financial formulas before publication, and every calculator can be embedded on any website with one line of HTML, free forever.
Features
- 25 interactive calculators: mortgages (recast, points, refinance break-even, amortization), debt (snowball vs avalanche, credit card minimums), savings, retirement/FIRE
- 100% client-side computation — your numbers never leave your browser
- No sign-up; private calculator inputs; no analytics or ads inside embeds
- Assumptions stated next to every result
- Math verified against closed-form financial formulas
- Embeddable on any site with one line of HTML (free, attribution link included)
- Static pages, system fonts, a few KB of vanilla JS each — instant load
Use Cases
- See your real mortgage payoff date with extra payments or a lump sum
- Compare debt snowball vs avalanche with your actual debts — payoff dates, total interest, verdict
- Find out what minimum payments on a credit card really cost (and how long they take)
- Decide rent vs buy over your true time horizon, with the down payment's opportunity cost included
- Check how much house you can afford by the 28/36 rule lenders use
- Compute your FIRE number with an adjustable withdrawal rate
- Embed any calculator in your blog, class page, or client site — free
- Every calculation runs entirely in your browser — the numbers you type never leave it. The site uses aggregate traffic analytics; embeds contain no analytics or ads.
Comments
Hi Fazier 👋 I built MoneyCrunchLab after noticing that most financial calculators online are either ad-walled quiz funnels or worked examples with someone else's numbers. So I set myself three constraints and stuck to them: everything computes in your browser (the numbers you type never leave it — there's no backend to send them to), no sign-up and no tracking anywhere, and every calculator states its assumptions right next to the results. The comparison tools will even tell you when the "wrong" answer wins — the rent-vs-buy calculator has no problem telling you to keep renting. 25 calculators so far (mortgages, debt payoff, savings, retirement), each verified against closed-form financial formulas before publication. And every one of them embeds on any website with a single line of HTML, free forever — that part is for the bloggers and teachers here. If you find a number that looks wrong, tell me: I'll show the math or fix it within the day. That's the whole editorial policy. — Pierre-Antoine, indie maker at SilverBack Studio
The financial decision-making friction moneycrunchlab solves is genuinely valuable. Most people avoid running the numbers because calculators either require sign-ups, leak your data, or are buried inside finance apps that focus on selling products. Having 25 specialized calculators right here - mortgages, debt, savings, retirement - all running in-browser with zero tracking means you can actually model scenarios without friction. The fact that every calc states its assumptions and shows the losing side of trade-offs builds real trust. For content creators especially who embed financial tools in blogs or guides, this is huge - one line of HTML, zero backend costs, zero tracking for your readers. The transparency about what each calculator does and why it matters is a breath of fresh air in an industry that hides complexity.
moneycrunchlab has great potential and offers some useful features, but I encountered a few issues that could be improved. Please contact me so I can share detailed feedback and suggest the changes I'd like to see. Email: [email protected]
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Comments
Hi Fazier 👋 I built MoneyCrunchLab after noticing that most financial calculators online are either ad-walled quiz funnels or worked examples with someone else's numbers. So I set myself three constraints and stuck to them: everything computes in your browser (the numbers you type never leave it — there's no backend to send them to), no sign-up and no tracking anywhere, and every calculator states its assumptions right next to the results. The comparison tools will even tell you when the "wrong" answer wins — the rent-vs-buy calculator has no problem telling you to keep renting. 25 calculators so far (mortgages, debt payoff, savings, retirement), each verified against closed-form financial formulas before publication. And every one of them embeds on any website with a single line of HTML, free forever — that part is for the bloggers and teachers here. If you find a number that looks wrong, tell me: I'll show the math or fix it within the day. That's the whole editorial policy. — Pierre-Antoine, indie maker at SilverBack Studio
The financial decision-making friction moneycrunchlab solves is genuinely valuable. Most people avoid running the numbers because calculators either require sign-ups, leak your data, or are buried inside finance apps that focus on selling products. Having 25 specialized calculators right here - mortgages, debt, savings, retirement - all running in-browser with zero tracking means you can actually model scenarios without friction. The fact that every calc states its assumptions and shows the losing side of trade-offs builds real trust. For content creators especially who embed financial tools in blogs or guides, this is huge - one line of HTML, zero backend costs, zero tracking for your readers. The transparency about what each calculator does and why it matters is a breath of fresh air in an industry that hides complexity.
moneycrunchlab has great potential and offers some useful features, but I encountered a few issues that could be improved. Please contact me so I can share detailed feedback and suggest the changes I'd like to see. Email: [email protected]
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