About MortgageMathLab
A NumbersLab project — data-driven financial tools and analysis
NumbersLab builds free, data-driven financial calculators and comparison tools that help people make smarter money decisions. Every tool we build is powered by real market data — Zillow Home Value Index (ZHVI) and Observed Rent Index (ZORI) for housing prices, IRS data for tax brackets, NAIC data for insurance costs, and county assessor records for property taxes. We don't guess. We calculate.
MortgageMathLab is our flagship mortgage resource: 22+ free calculators, 50 state guides, 750+ city pages, 1,225 state comparisons, and in-depth homebuyer education — all built to give you accurate answers without asking for your phone number or personal information. It's part of a portfolio of four financial tools sites, a Chrome extension, and a weekly newsletter — all focused on the same mission: making financial data accessible to everyone, not just professionals.
We publish The Numbers Letter — a free weekly newsletter covering real estate investing data, market analysis, and financial tool updates. We also share data breakdowns and tool walkthroughs on our YouTube channel. For more background on the founder and team, connect with us on LinkedIn.
The NumbersLab Portfolio
Free financial tools — each focused on making a specific financial decision clearer:
Free weekly newsletter: real estate investing data, market analysis, deal breakdowns with real numbers, and financial tool updates. No spam, no fluff.
Subscribe Free →How MortgageMathLab Makes Money
MortgageMathLab is supported by advertising through Google AdSense. This is what keeps every tool, calculator, and article on this site completely free. We do not sell your data. We do not accept payment from lenders to influence calculations or recommendations. The numbers you see are the real numbers — no hidden agenda.
Our Data
Our housing data comes from Zillow's ZHVI (Home Value Index) and ZORI (Observed Rent Index), U.S. Census Bureau records, and state housing finance agency reports. Property tax rates are sourced from county assessor offices. Closing cost and transfer tax data comes from state-level surveys. Insurance estimates use NAIC (National Association of Insurance Commissioners) data and state-level industry averages. All data is updated regularly to reflect current market conditions.
Contact
Have a question, found a data error, or want to discuss a partnership? Reach out: