Investment
Updated August 5, 2026
Growing wealth starts with understanding how your money compounds over time. This hub organizes every PraxisCalc investment calculator and guide in one place, whether you're investing a fixed amount every month, deploying a lump sum, or comparing the two.
A Systematic Investment Plan (SIP) spreads your investment across regular monthly contributions, while a lump sum deploys capital all at once. Both rely on the same underlying compounding math, just applied differently.
Project monthly investment growth
Model a single large investment
Compare both strategies side by side
Compound interest is the single most powerful force in long-term investing: your returns start earning their own returns. CAGR (Compound Annual Growth Rate) is the standard way to measure and compare an investment's smoothed annual growth rate.
See your money grow over time
Calculate non-compounding interest
Measure annualized growth rate
Once you've made an investment, ROI (Return on Investment) and annuity math help you measure efficiency and plan for recurring payouts, such as retirement income streams.
Percentage, formula & annualized return
Future value of an ordinary annuity
Whether you're just starting your first SIP or comparing lump-sum deployment against dollar-cost averaging, start with the calculator that matches your question today, then use the linked guide to understand the formula behind the number.
Each guide below answers one calculation question directly, shows the formula, and works through a real example you can reproduce.
The ROI formula, annualised return over multiple years, and how marketing and project ROI differ.
Compound annual growth rate, why it beats a simple average, and the off-by-one year error to avoid.
The A = P(1 + r/n)^(nt) formula, how compounding frequency changes the result, and the rule of 72.
Where the two diverge, and why the gap on $10,000 over 30 years is larger than most people expect.
The annuity formula behind a systematic investment plan, and how to solve for a monthly target.
The lump sum formula, and when investing all at once beats spreading the same money monthly.
Valuing a stream of equal payments, and the difference between an ordinary annuity and an annuity due.
Combining an opening balance with regular deposits, and separating your contributions from growth.
How inflation erodes buying power, and what a fixed sum is really worth after 20 or 30 years.
Why the two rates differ, how to convert between them, and which one each side of a deal quotes.