Editorial Policy

Every calculator on CalcEngine is built using industry-standard formulas and methodologies. We use the same mathematical approaches that banks, financial institutions, and government agencies use:

• Mortgage & Loan Calculators: Standard amortization formula used by all US lenders
• Tax Calculators: IRS tax brackets, standard deductions, and FICA rates for the current tax year
• Retirement Calculators: Compound interest formulas with contribution limits from IRS Publication 590 and the Thrift Savings Plan
• Government Pay Calculators: Official GS pay tables from OPM and military pay charts from DFAS
• Social Security Estimator: SSA bend point formula and PIA calculation methodology

All calculator logic is covered by automated unit tests to ensure mathematical accuracy. Our test suite currently includes 89 tests across all calculation modules.

We source our data from official government publications and authoritative financial references:

• Tax Data: IRS Revenue Procedure (annual inflation adjustments)
• GS Pay Tables: Office of Personnel Management
• Military Pay: Defense Finance and Accounting Service
• Social Security: Social Security Administration
• Retirement Limits: IRS Retirement Topics
• Inflation Data: Bureau of Labor Statistics CPI

We update our calculators on a regular schedule:

• Annual (January): Tax brackets, standard deductions, 401(k)/IRA contribution limits, Social Security wage base, FERS/TSP limits, GS pay tables
• As Published: Military pay tables (typically January), locality pay adjustments
• Ongoing: Bug fixes, accuracy improvements, user-reported issues

Each calculator page displays a “Last Updated” date so you know when the data was last verified.

Our calculators are designed to provide useful estimates, but they have inherent limitations:

• Simplified Models: Real-world financial situations often involve factors our calculators don't capture (state-specific rules, individual circumstances, edge cases)
• Constant Assumptions: Many calculators assume constant rates of return, inflation, or contribution levels, which don't reflect real-world variability
• Federal Focus: Tax calculators use federal rates; state tax calculations are simplified estimates
• Point-in-Time Data: Interest rates, market conditions, and regulations change; calculators reflect data as of their last update

For major financial decisions, we recommend consulting with a qualified financial advisor, tax professional, or attorney who can account for your specific situation.