The Universal Calculation Engine
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The Universal Calculation Engine

Invest vs Pay Debt

Guaranteed “return” of paying off a card versus expected return in a 401(k)—after tax and risk.

Start this lessonWhat guaranteed payoff compares to in expected return

Frame both sides after tax

Paying off a 20% card is a guaranteed 20% improvement on that balance. Investing might average higher over decades—but not guaranteed, and not on the same timeline.

Order of operations many planners use

  1. Budget and emergency fund.
  2. 401(k) to the match.
  3. High-interest consumer debt.
  4. Other goals split between extra debt paydown and investments.

Put numbers next to each other

Mistakes

  • Investing while carrying revolving high-APR debt without a plan.
  • Prepaying a 3% mortgage while forgoing decades of tax-advantaged growth without a reason.

Use the calculator

FAQ

What about student loans?

Rate, forgiveness eligibility, and cash flow matter—treat as its own line item, not generic “debt.”