Private compounding lab
SIP & Step-Up Decision Engine
Compare standard SIP, step-up discipline, and delayed-start cost in one browser-side workspace.
Regular SIP
Step-Up SIP
The Price of Waiting
How much wealth you lose by delaying your start.
Total lost wealth compared to starting today.
đ Assumptions Used v1.1
View full assumptions changelog â
- Return Rate (Default 12%): Based on Nifty 50 CAGR (~12.7% over 20 years)
- Compounding: Monthly compounding assumed for SIP mode
- Inflation: Not adjusted. Real returns will be lower
- Taxes: LTCG tax (12.5% above âš1.25L) applies to equity mutual funds (Budget 2024-25)
- Expense Ratios: Not deducted. Direct funds: 0.5-1% lower than Regular
đ Official Data Sources
| Nifty 50 Returns | NSE India | Jun 2026 |
| Inflation (CPI) | MoSPI | Jun 2026 |
| LTCG Tax Rates | Income Tax India | Jul 2024 |
| PPF Interest Rate | NSI (MoF) | Jun 2026 |
| MF NAV Data | AMFI India | Daily |
âąī¸ Data last verified: 29 June 2026 | We update rates quarterly or when government announces changes.
Why do assumptions matter? â𧎠How This Calculator Works
Inputs:
- Monthly Investment (P): Amount you invest each month
- Expected Return (r): Annual return rate, divided by 12 for monthly
- Time Period (n): Number of years à 12 = months
Formula (Regular SIP):
Interpretation:
- Total Value: What your investment grows to.
- Invested: Sum of all contributions (P Ã n).
- Returns: Total Value minus Invested = gains from compounding.
Step-Up SIP applies an annual percentage increase to P, recalculating each year.
Understanding the Power of SIP in Mutual Funds
A Systematic Investment Plan (SIP) is a method of investing in mutual funds where an investor contributes a fixed amount regularly. Over time, this benefits from Rupee Cost Averaging and the Power of Compounding. Our SIP calculator helps you visualize how even a small monthly contribution can grow into a significant corpus over 10, 20, or 30 years.
How to use the SIP & Step-Up Calculator?
- Monthly Investment: Enter the amount you plan to invest every month.
- Expected Return: Input the annual return rate (Equity usually averages 12-15% over long terms).
- Investment Duration: Choose how many years you plan to stay invested.
- Step-Up %: (Optional) Enter the percentage by which you'll increase your SIP every year as your income grows.
Comparison: Regular SIP vs Step-Up SIP
A regular SIP keeps your contribution constant. However, a Step-Up SIP (increasing your investment by say, 10% every year) can lead to a radically larger retirement corpus. Our calculator provides a side-by-side comparison to show you exactly how much "future wealth" you are creating by being disciplined.