Methodology

FounderMath calculators use deterministic formulas documented on each tool page. The calculators are designed for educational planning, not exact legal or cap-table administration.

Formula standards

• Use plain formulas that can be inspected and tested.
• Show important assumptions near calculator results or explanatory sections.
• Prefer conservative simplified models over pretending to model every legal document variation.
• Reject or warn on impossible inputs such as negative investments or 100% investor ownership.

Review standards

Each calculator should have known test cases, edge-case tests, browser smoke tests, mobile checks, and visible last-reviewed dates. Finance-adjacent material is reviewed for disclaimers, unsupported claims, and language that could sound like legal, tax, accounting, investment, or fundraising advice.

Limitations

Startup financing terms vary by document, jurisdiction, capitalization definition, option-pool treatment, and negotiation. SAFE and convertible-note calculations in particular can change materially based on exact terms. FounderMath outputs are estimates for understanding concepts.

See Sources for source categories used when validating terminology and assumptions.

Last reviewed July 18, 2026.