Calculation Methodology

Federal tax is estimated with a progressive tax delta: tax(income + taxable conversion) minus tax(income).

Taxable conversion uses a pro-rata basis estimate: conversion amount multiplied by one minus basis divided by IRA balance.

The default assumption is that conversion taxes are paid from outside funds.

IRMAA, ACA subsidies, NIIT, AMT, RMDs, credits, and state-specific rules are outside the MVP calculation scope.

Primary references: IRS Publication 590-A, IRS Publication 590-B, and IRS tax inflation adjustments for tax year 2026.

Tax data freshness

Tax year 2026, reviewed May 2026. Federal calculations are educational estimates based on the inputs provided by the user.

Source basis: IRS annual tax inflation adjustments and retirement account publications. Updated within 15 business days after new annual IRS tax tables are released.

Not modeled: IRMAA, ACA subsidies, NIIT, AMT, tax credits, state-specific deductions.

2026 Federal Tax Brackets Used

The calculator uses a progressive tax delta method. These brackets are included so users can verify the tax-year assumptions.

Single

From	To	Rate
$0	$12,400	10%
$12,400	$50,400	12%
$50,400	$105,700	22%
$105,700	$201,775	24%
$201,775	$256,225	32%
$256,225	$640,600	35%
$640,600	No limit	37%

Married filing jointly

From	To	Rate
$0	$24,800	10%
$24,800	$100,800	12%
$100,800	$211,400	22%
$211,400	$403,550	24%
$403,550	$512,450	32%
$512,450	$768,700	35%
$768,700	No limit	37%

Married filing separately

From	To	Rate
$0	$12,400	10%
$12,400	$50,400	12%
$50,400	$105,700	22%
$105,700	$201,775	24%
$201,775	$256,225	32%
$256,225	$384,350	35%
$384,350	No limit	37%

Head of household

From	To	Rate
$0	$17,700	10%
$17,700	$67,250	12%
$67,250	$105,700	22%
$105,700	$201,750	24%
$201,750	$256,200	32%
$256,200	$640,600	35%
$640,600	No limit	37%