Investment Calculator
Overview
Project investment growth with compound interest, calculate retirement savings, and plan for financial goals
Key Facts
| Field | Value |
|---|---|
| Calculator ID | investment |
| Category | Finance |
| Vertical | Finance & Economics |
| App route | /verticals/finance/investment |
| API endpoint | /api/public/calculate?id=investment |
Inputs
| Input ID | Label | Type | Required | Default | Constraints |
|---|---|---|---|---|---|
principal | Starting Principal | currency | Yes | 10000 | min 0, max 10000000, step 1000 |
monthlyContribution | Monthly Contribution | currency | Yes | 500 | min 0, max 100000, step 50 |
annualRate | Annual Interest Rate | percent | Yes | 8 | min 0, max 50, step 0.1 |
years | Time Horizon | number | Yes | 20 | min 1, max 50, step 1 |
compoundFrequency | Compound Frequency | select | Yes | 12 | - |
How to Use
- Enter Starting Amount — Input your current investment balance or starting amount if beginning from zero.
- Set Monthly Contribution — Enter how much you can invest each month. Consistency is key - even $100/month compounds significantly.
- Choose Return Rate — Use 7% for conservative estimate (inflation-adjusted), 10% for historical stock market average.
- Set Time Horizon — Enter investment duration in years. Longer timelines = more compound growth and lower risk.
Result Surfaces
| Output | Display Type | Format |
|---|---|---|
| Computed results | result-card | - |
Related Calculators
FAQ
What return rate should I use for investments?
Historical stock market average is 10% nominal, 7% after inflation. For conservative estimates, use 6-7%. Bonds return 4-5%. A balanced 60/40 portfolio averages 7-8%.
How much should I contribute to my 401k?
At minimum, contribute enough to get full employer match (typically 3-6% of salary) - this is free money with 100% instant return. Ideal target is 15-20% of gross income for retirement.
Roth IRA or Traditional IRA?
Roth: Pay taxes now, tax-free withdrawals later (better if you expect higher tax bracket in retirement). Traditional: Tax deduction now, pay taxes later (better if you expect lower tax bracket in retirement). Many people do both.
Evidence
src/lib/calculators/registry.ts(metadata)src/lib/calculators/page-registry.ts(page/HowTo metadata)src/lib/calculators/finance/investment.ts(calculator config)
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