Finance
Investment calculator
The most motivating part of investing is watching compounding take over, and the clearest way to see it is to run the numbers. Enter a starting amount, a monthly contribution, an expected annual return, and a time horizon. The calculator projects the future value with monthly compounding and splits the result into what you contributed versus what growth added. Use it for retirement planning, a brokerage account, or comparing what an extra $100 a month is worth over 20 years.
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Investment Calculator
Project the growth of a one-time investment plus ongoing monthly contributions.
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Investment journalRecord contributions and assumptions alongside your estimates.Paid link · Check current price ↗As an Amazon Associate I earn from qualifying purchases.The math, plainly
How it works
- 01
The starting balance compounds monthly at your expected annual return.
- 02
Each monthly contribution is treated as an end-of-month deposit earning the same rate.
- 03
Investment growth is the projected value minus everything you contributed — the part compounding did on its own.
Try a real scenario
20-year plan
Inputs$10,000 start, $500/month, 7% annual return
ResultRoughly $301,000 projected value from $130,000 contributed.
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