Free Tools

Index Investing Calculators

Free, no-signup calculators for common index-investing decisions. Each tool documents its formula and assumptions directly on the page — see our calculator methodology.

Growth

Compound Interest Calculator

Project how a lump sum or recurring contribution grows over time at a given return rate.

Costs

Index Fund Fee Drag Calculator

See exactly how much a fund's expense ratio costs you in dollar terms over decades.

Retirement

Roth vs. Traditional IRA Calculator

Compare estimated after-tax outcomes between a Roth and Traditional account.

Retirement

Retirement Savings Projector

Estimate whether your current savings rate is on track for a target retirement age.