Sources & methodology

Last updated: August 5, 2026

Every formula behind a DoCalc calculator is a documented, industry-standard calculation — not something we invented. This page lists the authoritative sources we draw on, by category, and links to individual articles with fuller citations. See our Editorial Policy for how we research and verify these before publishing.

SaaS & startup metrics

Our SaaS calculators (MRR/ARR, CAC payback, LTV:CAC, churn, NRR/GRR, Rule of 40, and related metrics) follow the definitions used across subscription-billing and revenue-recognition practice, and are benchmarked against research published by:

• ChartMogul — SaaS Metrics glossary — formula definitions for MRR, ARR, churn, and retention metrics.
• SaaS Capital — SaaS benchmarking research — growth, retention, and Rule of 40 benchmarks for private SaaS companies.
• Bessemer Venture Partners — State of the Cloud — public and private SaaS growth and efficiency benchmarks.

Individual calculators and blog posts (e.g. MRR vs ARR, Rule of 40, CAC Payback Period) include a "Sources & further reading" section at the bottom with the specific citations used for that topic.

Personal & consumer finance

Our finance calculators (mortgage payment, loan payoff, compound interest) follow standard amortization and compounding formulas used across lending and personal finance, cross-checked against:

• Consumer Financial Protection Bureau (CFPB) — mortgage and loan disclosure standards, amortization mechanics.
• Investor.gov (U.S. SEC) — compound interest methodology.
• Freddie Mac Primary Mortgage Market Survey — reference mortgage rate context.

Insurance

Our Life Insurance Needs calculator follows the DIME method (Debts, Income, Mortgage, Education), a coverage-estimation approach widely taught by financial planners. Our Auto and Home Insurance calculators apply commonly-cited relative rating factors — not a specific insurer's actual pricing model — to a baseline premium you provide, and are clearly labeled as estimates rather than quotes.

• Insurance Information Institute (III) — general auto and home insurance rating factor education.
• National Association of Insurance Commissioners (NAIC) — insurance regulatory and consumer information.

Real estate (in progress)

Real Estate calculators are on our roadmap (see the changelog). When they launch, this section will list the specific sources behind them.

How to verify a specific calculator

Every calculator page includes plain-language explanations of its formula directly on the page — we don't hide the math behind a black box. If a calculator's source isn't obvious from its own page, or you want to double-check a citation, email support@docalc.net and we'll point you to it directly.