Roth Conversion Calculator
Calculate the tax cost of converting Traditional IRA or 401(k) funds to a Roth IRA. Strategic conversions can reduce lifetime taxes and eliminate Required Minimum Distributions.
Roth Conversion Basics
| Traditional IRA | Roth IRA |
|---|---|
| Tax-deferred growth | Tax-free growth |
| Taxable withdrawals | Tax-free withdrawals |
| Required Minimum Distributions (RMDs) | No RMDs during lifetime |
| Tax deduction on contributions | No upfront tax benefit |
When to Convert
| Best Time to Convert | Why |
|---|---|
| Low-income years | Pay less tax on conversion |
| Early retirement | Before Social Security starts |
| Market downturns | Convert more shares for same tax |
| Pre-RMD age | Reduce future mandatory withdrawals |
| Low tax bracket years | Maximize tax savings |
Roth Conversion Calculator
``javascript
function calculateRothConversion(conversionAmount, currentIncome, filingStatus = 'single') {
// Current taxable income
const standardDeduction = filingStatus === 'married' ? 29200 : 14600;
const currentTaxableIncome = Math.max(0, currentIncome - standardDeduction);
// Income after conversion
const newTaxableIncome = currentTaxableIncome + conversionAmount;
// Calculate marginal tax on conversion
const taxBefore = calculateFederalTax(currentTaxableIncome, filingStatus);
const taxAfter = calculateFederalTax(newTaxableIncome, filingStatus);
const conversionTax = taxAfter - taxBefore;
// Effective rate on conversion
const effectiveRate = (conversionTax / conversionAmount) * 100;
return {
conversionAmount,
conversionTax: conversionTax.toFixed(2),
effectiveRate: effectiveRate.toFixed(2) + '%',
newMarginalBracket: findBracket(newTaxableIncome, filingStatus),
netToRoth: (conversionAmount - conversionTax).toFixed(2)
};
}
``
Conversion Tax Examples (Single, $50k Current Income)
| Conversion | Tax Cost | Effective Rate |
|---|---|---|
| $10,000 | $1,200 | 12% |
| $25,000 | $3,660 | 14.6% |
| $50,000 | $8,010 | 16.0% |
| $100,000 | $19,510 | 19.5% |
Roth Conversion Strategies
- Bracket filling: Convert up to top of current bracket annually
- Multi-year approach: Spread large conversions over several years
- Market timing: Convert during market dips (more shares, same tax)
- Pre-retirement: Convert before Social Security increases income