How our calculators work
Every number on MoneyBert traces back to a documented formula and a named source. Here’s exactly how we build and check our tools.
Where our formulas come from
Our calculators use the same standard formulas used across the financial industry, not custom or simplified shortcuts. For example, our mortgage and loan calculators use the standard amortization formula lenders use to calculate principal and interest; our retirement calculators use standard compound-growth formulas with adjustable contribution and return assumptions you control.
Where our data and assumptions come from
Where a calculator depends on a rate, limit, or threshold set by law or policy (like tax brackets or contribution limits), we cite the specific government source and the year that figure applies to.
Sources we draw from
IRS.gov for tax brackets, deduction limits, and retirement contribution caps · Consumer Financial Protection Bureau for lending and mortgage guidance · Social Security Administration for benefit estimation rules · Federal Reserve economic data for historical rate context
How often we update
Tax brackets, contribution limits, and similar figures change annually. We review every calculator that depends on these figures each year when the new figures are published, and we note the last-reviewed date at the bottom of each calculator page.
What our calculators are, and aren’t
These tools are built to help you understand your options and estimate outcomes. They are not personalized financial, tax, or legal advice, and results are estimates, not guarantees. Your actual numbers may differ based on details a general calculator can’t account for. For decisions with real financial consequences, we’d encourage you to confirm specifics with a qualified professional.
Who builds and reviews this content
MoneyBert is built and maintained by one person — me. I run an e-commerce business and have spent considerable time studying financial markets and risk management in depth, which means precision in numbers isn’t optional in my day-to-day life. Every calculator here gets built with that same standard: real formulas, cited sources, no shortcuts. I review and update each tool as tax rules, contribution limits, and other figures change each year. More about me on the About page.
Something look wrong?
If you spot an error in a calculation or an outdated figure, let us know — we check and correct these promptly.