Editorial principles
- Every formula and figure is verified against official sources (laws and public agency notices).
- When rates change, the calculator and its guide content are updated together.
- Reported errors are fixed as soon as they are confirmed.
Calculators by Sin Dongho (178)
-
Auto
Monthly Car Cost Calculator
Free monthly car cost calculator using AAA Your Driving Costs methodology. Total cost of ownership includes fuel, insurance, registration, and maintenance — for gas, diesel, hybrid, and EV.
-
Developer Tools
Color Palette Generator
Free color palette generator. Pick a base HEX color and instantly get six harmony types: complementary, analogous, triadic, tetradic, split-complementary, and shades.
-
Education
Course Credit Planner
Free course credit planner. Track progress toward your bachelor's degree by completed credit hours and project semesters remaining at your typical course load.
-
Real Estate
Mortgage Affordability Calculator
Free mortgage affordability calculator using debt-to-income (DTI) ratios. Find maximum home price by income, debts, down payment, and current mortgage rate.
-
Real Estate
Fixed vs ARM Mortgage Comparison
Free fixed vs ARM mortgage comparison calculator. Compare 30-year fixed to 5/1, 7/1, and 10/1 ARM scenarios — see total cost over expected stay duration.
-
Real Estate
Home Sale Net Proceeds Calculator
Free home sale net proceeds calculator. Estimate cash to seller after agent commission, transfer tax, mortgage payoff, closing costs, and capital gains tax (Section 121 exclusion).
-
Taxes
Rental Income Tax Calculator
Estimate federal + state tax on rental property income with full IRS rules: 27.5-year depreciation, passive activity loss limits, QBI 20% deduction, NIIT 3.8%, and REPS deduction.
-
Real Estate
Rent-to-Income Ratio Calculator
Free rent-to-income ratio calculator. Find affordable rent based on the 30% rule and lender 3× rent rule. HUD defines housing-cost burden at 30%+ of income.
-
Real Estate
Vacancy-Adjusted Rental Yield Calculator
Free vacancy-adjusted rental yield calculator. Realistic rental property cap rate after accounting for typical 5-10% vacancy in US rental markets, plus turnover costs.
-
Real Estate
Buy vs Rent Calculator
Free buy vs rent comparison calculator. Compare 5-30 year cost of buying vs. renting using mortgage, property tax, maintenance, opportunity cost, and home appreciation.
-
Real Estate
Multi-Property Investment Tax Calculator
Free rental property tax calculator covering multiple properties. Models Schedule E income, 27.5-year depreciation, Section 199A QBI 20%, passive activity loss, and cost segregation savings.
-
Real Estate
Home Breakeven Appreciation Calculator
Free home breakeven appreciation calculator. Calculate the minimum sale price (and annual appreciation rate) you need to break even after closing costs and 6% real estate commissions.
Showing 97–108 of 178