Methodology
mycalcstool publishes browser-based calculators. We document the main formulas, tax assumptions, and reference sources that influence the output so users can understand what the estimate includes and what it leaves out.
Finance calculators
Mortgage Calculator uses standard amortization formulas and can add property tax, insurance, PMI, and HOA fees.
Salary Calculator uses 2026 federal tax brackets, standard deductions, FICA rules, and state tax tables stored in the project data files.
Compound Interest Calculator combines the selected compounding frequency with recurring contributions to estimate future value.
Health and utility calculators
Health calculators use public reference formulas such as BMI or TDEE equations and should be treated as educational estimates only.
Utility calculators use direct mathematical conversions and arithmetic, but input context still matters.
Reference sources
- IRS, Social Security Administration, and state tax agencies for US payroll and tax rules
- National Tax Service, National Pension Service, National Health Insurance Service, and Employment Insurance guidance for Korean calculators
- Publicly available reference equations for BMI, TDEE, due date, and related health estimates
Limits of the result
Calculator outputs are estimates, not legal, medical, tax, or financial advice.
Rates, rules, and deduction limits can change. Important decisions should be verified with an official source or licensed professional.
If you spot an outdated rule or formula, send the source and page URL through the Contact page.