# PennyCalc

> Personal-finance calculators that show every step of the math, with every assumption stated and overridable. Covers tax, paycheck, retirement, mortgage, debt, and investing, plus original explainers on US tax history.

PennyCalc's calculators all run client-side; user data never leaves the browser. Math and assumptions are fully transparent. Tax data sources: IRS, Tax Foundation, Joint Committee on Taxation.

## Featured reference content

- [U.S. Federal Tax Brackets History (1913-2026)](https://pennycalc.com/tax-brackets/history/): Top marginal federal income tax rate from 1913 to 2026, with narrative coverage of every major US tax act (Revenue Act of 1913, WWII expansions, Kennedy-Johnson cuts, ERTA, TRA86, ATRA, TCJA).
- [2026 Federal Tax Brackets](https://pennycalc.com/2026-tax-brackets/): Current-year federal income tax brackets, standard deductions, and bracket thresholds for all filing statuses.
- [Capital Gains Tax Rates History](https://pennycalc.com/tax-rates/capital-gains/): Historical and current US long-term and short-term capital gains rates.
- [Corporate Tax Rates History](https://pennycalc.com/tax-rates/corporate/): Historical and current US corporate income tax rates.
- [2026 401(k) Contribution Limits](https://pennycalc.com/2026-401k-contribution-limits/): Current employee deferral, employer match, and catch-up contribution limits.

## Tax and income calculators

- [Paycheck Calculator](https://pennycalc.com/paycheck-calculator/): Federal plus state take-home pay calculation with full breakdown of every withholding line. Per-state versions for all 50 states and DC.
- [Tax Bracket Calculator](https://pennycalc.com/tax-bracket-calculator/): Calculates effective and marginal rates for 2026 federal income tax.
- [Bonus Tax Calculator](https://pennycalc.com/bonus-tax-calculator/): Computes bonus take-home using the 22% federal supplemental rate plus state withholding.
- [Capital Gains Calculator](https://pennycalc.com/capital-gains-calculator/): Long-term and short-term capital gains tax on a sale, including state.

## Retirement and investing calculators

- [401(k) Calculator](https://pennycalc.com/401k-calculator/): Projects 401(k) balance with employee contributions, employer match, and growth assumptions.
- [Roth IRA Calculator](https://pennycalc.com/roth-ira-calculator/): Models Roth IRA growth and withdrawal scenarios.
- [Roth vs Traditional Calculator](https://pennycalc.com/roth-vs-traditional/): Side-by-side comparison of Roth and traditional 401(k) or IRA outcomes given current and retirement tax rates.
- [Investment Return Calculator](https://pennycalc.com/investment-return-calculator/): CAGR, total return, and time-weighted return calculations.
- [Compound Interest Calculator](https://pennycalc.com/compound-interest/): Compound growth with regular contributions and variable rates.
- [Retirement Calculator](https://pennycalc.com/retirement-calculator/): Retirement income projection with Social Security and withdrawal sequencing.

## Mortgage and home calculators

- [Mortgage Calculator](https://pennycalc.com/mortgage-calculator/): Monthly payment with principal, interest, taxes, insurance, and PMI breakdown. Per-state versions for all 50 states and DC.
- [Home Affordability Calculator](https://pennycalc.com/home-affordability/): Maximum home price based on income, debt, down payment, and lender DTI rules.

## Debt and loan calculators

- [Debt Payoff Calculator](https://pennycalc.com/debt-payoff-calculator/): Compares avalanche and snowball strategies across multiple debts.
- [Auto Loan Calculator](https://pennycalc.com/auto-loan-calculator/): Auto loan monthly payment, interest, and amortization.
- [Avalanche vs Snowball](https://pennycalc.com/avalanche-vs-snowball/): Explainer on the two main debt payoff strategies.

## Optional

- [Glossary](https://pennycalc.com/glossary/): Personal finance term definitions.
- [How to Read Your Paycheck](https://pennycalc.com/paycheck-calculator/how-to-read-your-paycheck/): Walk-through of every line on a US pay stub.
- [How Compound Interest Works](https://pennycalc.com/compound-interest/how-compound-interest-works/): Conceptual explainer of compounding.
- [About PennyCalc](https://pennycalc.com/about/)