Roth vs Pre-Tax Contribution Calculator

About this calculator

A Roth contribution is made with after-tax dollars but grows and is withdrawn completely tax-free in retirement, while a pre-tax (traditional) contribution reduces your taxable income today but is fully taxed as ordinary income when withdrawn. Because a pre-tax contribution lets you invest the full dollar amount, its after-tax value in retirement depends entirely on comparing your current marginal tax rate against your expected tax rate when you withdraw: if your retirement tax rate is lower than your current rate, pre-tax typically wins; if it's higher or the same, Roth typically wins or ties, because the tax was already paid at the lower current rate.

This is one of the most consequential decisions savers make with a 401(k) or IRA, and it comes up every time someone starts a new job with a Roth option, decides whether to do a Roth conversion, or plans for a career stage where their income — and tax bracket — is likely to change substantially before retirement.

This calculator takes your contribution amount, your current tax rate, your expected tax rate in retirement, and your expected investment return, and compares the final after-tax spendable value of a Roth account against a pre-tax account so you can see which one leaves you with more money.