About GrowCompass

What this is

GrowCompass is a free, no-signup compound interest calculator. Enter a starting balance and a monthly contribution, set the rate and time, and immediately see the future value, exactly how much of it came from compounding, a year-by-year schedule, and a goal planner that works the maths backwards. Everything runs in your browser; nothing you enter is stored or sent anywhere.

Why we built it

Most "investment calculators" online are either lead-gen funnels dressed as tools, or they bury the mechanics in assumptions you can't see. We wanted the opposite: one clean page, the standard closed-form formulas applied in the open, and a side-by-side compound-vs-simple view that shows where the growth actually comes from.

How we keep the maths honest

• Growth uses A = P(1 + r/n)^nt — the same formula every finance textbook and bank statement uses.
• Contributions are handled with the future-value-of-an-annuity formula, and the compounding frequency you choose sets the effective monthly rate.
• Time-to-goal is solved with logarithms rather than simulated month by month, so a 50-year plan is as exact as a 1-year plan.
• Because real investing involves taxes, fees and volatile returns, every projection is clearly labelled as a constant-rate estimate — and the assumptions are spelled out on the calculator page.

What it isn't

GrowCompass is not a broker, robo-advisor, or financial planner, and it is not affiliated with any bank or government agency. The figures are educational projections, not investment advice or return guarantees. For anything you'd act on, consult your account documents or a qualified financial professional.

Free and private

The tool is completely free and runs entirely in your browser — no account, no email wall, and no tracking of what you enter. Your balances, rates and goals never leave your device.