MoneyCrunchLab is a collection of free financial calculators built and maintained by SilverBack Studio, a French independent software studio. Each tool is built from the standard amortization and time-value-of-money formulas used by financial products and spreadsheets, then explained in plain English on the page with its main assumptions.
The calculators are estimates for educational purposes. They are not financial advice, and they can’t know your full situation — for decisions involving significant amounts, talk to a qualified professional.
Who’s behind it
MoneyCrunchLab is written and maintained by Pierre-Antoine Beugnot, a software engineer and the founder of SilverBack Studio. He is not a financial advisor and doesn’t pretend to be one — this site deliberately stays in the lane where an engineer belongs: the math itself. Payoff timelines, break-evens, amortization tables, sourced statistics — computed from the values you enter under assumptions stated next to the result. What the numbers mean for your life is a conversation for a qualified professional; the model and its limits should remain inspectable here.
Questions, corrections, or a custom scenario for an article? Email hello@moneycrunchlab.com. Messages are answered personally.
Our methodology
Each calculator answers a bounded math question with a deterministic model: the same inputs produce the same result. The result is not generated by an AI system, a lender quote feed, or a hidden eligibility model. The editorial process was last reviewed on .
How a calculator is validated
- Define the question and units. The model starts with a specific decision or comparison, then states whether rates, dollars, payments, and time periods are nominal, effective, monthly, annual, or inflation-adjusted.
- Implement the model separately from the page. Amortization, compounding, payoff simulation, and comparison rules live in shared model code so the interface does not become a second source of financial logic.
- Test reproducible outputs and failure cases. Automated tests compare deterministic model outputs with reproducible reference cases and exercise conditions such as zero rates, non-amortizing payments, payoff limits, negative inputs, and rounding boundaries where they apply. A passing test is evidence that the code matches those defined cases, not that a scenario predicts a person’s outcome.
- Review the page against the model. The method, worked example, exclusions, and source links shown on each calculator are checked against the same model used by the interface. A real editorial review date is then published on the page.
Source hierarchy
For rules and consumer disclosures, we prefer the primary authority: U.S. agencies and regulators such as the CFPB, IRS, SEC, Federal Reserve, BLS, or Department of Education. Program and servicing mechanics use the relevant first-party guide, such as Fannie Mae, Freddie Mac, or a federal loan program. Research-based planning assumptions link to the original study where available. Secondary articles may help locate a question, but they do not establish a rule when a primary source exists. A citation supports the stated concept; it does not turn a simplified calculator into an official disclosure or professional recommendation.
Assistance tools and editorial responsibility
Development, testing, research triage, and draft wording may use code analysis, automation, or AI-assisted tools. Those tools are not treated as authorities. Before publication, formulas are tied to deterministic model code, worked examples are reproduced by that code, and claims about rules or programs are checked against the linked source. Pierre-Antoine Beugnot retains final editorial responsibility for what appears on MoneyCrunchLab.
Privacy and corrections
Calculations run in your browser, and the site does not submit the numbers you type to a calculation backend. See the privacy policy for hosting requests, analytics, advertising, and legacy shared links.
If a result appears wrong, email the exact inputs, the displayed result, and the result you expected. We reproduce the case, distinguish a model defect from an assumption or rounding difference, add or update a test when the model is wrong, correct the page, and change the review date only after that re-check. Published review dates document when page content was last re-checked. Source code history is maintained privately by SilverBack Studio.
Spotted an error, or want a calculator that doesn’t exist yet? Email hello@moneycrunchlab.com.