SIP Calculator with Inflation Impact
Plan your investment growth with precision. Understand real purchasing power with inflation adjustments, combine regular SIPs with lump sums, and compare multiple scenarios side-by-side.
SIP Deep Dive
The math behind monthly investing
A SIP is a stream of monthly investments, each compounding for a different length of time — your first installment compounds for the full tenure, your last for barely a month. The future value formula is FV = P × [((1 + i)ⁿ − 1) / i] × (1 + i), where P is the monthly amount, i the monthly rate (annual ÷ 12), and n the number of installments. The consequence worth internalizing: in long SIPs, the early years do most of the compounding work. In a 20-year SIP at 12%, the first five years of installments contribute roughly 45% of the final corpus despite being only 25% of the money invested.
That's also why the single most powerful variable isn't the amount or even the return — it's tenure. ₹10,000/ month at 12% builds ₹23 lakh in 10 years, ₹50 lakh in 15, ₹1 crore in 20, and ₹1.9 crore in 25. Each extra five years roughly doubles the outcome, with zero extra monthly effort.
A worked example — flat vs step-up
Flat SIP: ₹15,000/month for 20 years at 12% grows to about ₹1.5 crore on ₹36 lakh invested. Now add a 10% annual step-up — raising the SIP each year as your income grows (₹15,000 → ₹16,500 → ₹18,150…). Total invested rises to ₹1.03 crore, but the corpus reaches roughly ₹2.9 crore — nearly double the flat outcome. The step-up is the single easiest upgrade in personal finance because it demands nothing today and automatically harvests every future raise.
The inflation check matters just as much: that ₹2.9 crore, deflated at 6% over 20 years, is worth about ₹90 lakh in today's purchasing power. Toggle the inflation adjustment in the calculator before deciding whether a projected corpus actually funds the goal you have in mind.
Rupee-cost averaging: real benefit, oversold story
Because a fixed amount buys more units when markets fall and fewer when they rise, SIPs average your purchase cost across market conditions — you never invest everything at a peak. This is a real risk-management benefit and, more importantly, a behavioral one: the automation keeps you investing through crashes, which is when future returns are actually bought. But be wary of the oversold version of this story — if you already have a lump sum, research consistently shows investing it immediately beats spreading it out about two-thirds of the time, because markets rise more often than they fall. SIP is the right tool for investing income as you earn it, not a superior strategy for deploying money you already have.
Choosing a realistic return assumption
Indian large-cap equity has delivered roughly 11–13% annualized over long periods; diversified and mid-cap funds somewhat more, with more violence along the way. Planning at 15%+ bakes disappointment into the plan. A sober framework: 12% for long-horizon equity SIPs, 10% if you want margin, 8% for balanced/hybrid funds — and always sanity-check the goal against the inflation-adjusted output, not the nominal one. If a goal only works at 15% returns, the honest fix is a bigger SIP or a longer runway, not a braver assumption.
Common mistakes
- Stopping the SIP in a crash — the installments bought at the bottom are the ones that generate outsized returns; pausing converts averaging into peak-only buying.
- Measuring SIP returns with CAGR. With monthly inflows there's no single starting value; your true return is XIRR — our IRR calculator computes it.
- Never stepping up. A salary that grows 8–10% yearly against a flat SIP means you invest a shrinking share of income every year without noticing.
- Running goal math in nominal terms. "₹1 crore for education in 18 years" is ~₹35 lakh in today's money at 6% inflation — size the goal in real terms first.
Build the full plan
Pair this tool with the retirement planner to size your target corpus, the time-to-1-crore calculator for milestone tracking, the SWP calculator for the withdrawal phase, and the compound interest calculator to see the underlying engine at work on lump sums.
Understanding Inflation Impact
What is Inflation? Inflation is the rate at which the general level of prices for goods and services rises, causing purchasing power to fall.
Real-World Example: If inflation is 6% annually, an item that costs ₹100 today will cost ₹106 next year. This means your ₹100 today will only buy ₹94 worth of goods next year.
Why it Matters: When projecting wealth over 10, 20, or 30 years, looking at nominal (unadjusted) numbers can be deceiving. A corpus of ₹1 Crore in 20 years will not buy you the same lifestyle as ₹1 Crore today.
- Always toggle "Show Inflation-Adjusted Returns" to see realistic purchasing power.
- Aim for investments that offer returns higher than the inflation rate (Real Returns).
- Use Step-Up SIPs to increase your investment amount as your income grows, countering inflation's effect.
Our comprehensive SIP Calculator features multiple tabs to help you plan, analyze, and compare your wealth strategies. Follow these steps:
Enter Baseline Inputs
In the Calculator tab, input your monthly investment, duration, and expected return rate. Use tooltips (ℹ️) for guidance.
Add Advanced Modifiers
Toggle Step-up SIP to model salary growth. Toggle Inflation to see real purchasing power. Add a Lump Sum if you are starting with initial capital.
Save as Scenario
Navigate to the What-If Analysis tab. Give your current calculation a name (e.g., "Aggressive 15%") and hit save. Repeat this by changing inputs to create up to 4 scenarios.
Compare & Decide
Open the Scenario Comparison tab to view side-by-side tables and bar charts. Find the optimal balance between your budget and financial goals.
For Beginners
Start simple. Enter ₹5,000 monthly for 15 years at 12%. Don't worry about inflation or step-ups yet. Just witness the power of compounding in the chart.
For Intermediate Planners
Include an initial lump sum you might have sitting in a bank account. Turn on Inflation Adjustment (around 6%) to ensure your final corpus actually covers your future expenses.
For Advanced Strategists
Heavily utilize the What-If Analysis. Create scenarios mapping a Conservative Portfolio (9%), Balanced (12%), and Aggressive (15%). Add a 10% annual Step-up to mimic career progression.
- Why is my real return so much lower? If you have inflation set at 6% over 20 years, purchasing power drops significantly. This is normal and emphasizes why equity investments are necessary to beat inflation.
- How to set realistic returns? Large Cap funds typically target 10-12%, Mid Caps 12-14%, and Small Caps 14-16% over the long term (10+ years).
- When to use Step-up? Always, if possible. Even a 5% step-up prevents your SIP from losing relative value to inflation over time.
What is a Systematic Investment Plan (SIP)?
SIP is a disciplined investment approach where you invest a fixed amount at regular intervals in a mutual fund, leveraging compounding and rupee cost averaging.
What's the difference between SIP and lump sum investment?
SIP involves spreading investments over time, reducing timing risk. Lump sum involves investing a large amount at once, better suited when markets are undervalued.
Can I combine a Lump Sum with my SIP?
Yes, our calculator allows you to enter an initial lump sum amount that compounds alongside your regular SIP investments, giving a unified final corpus.
Are the projected returns guaranteed?
No. Mutual fund investments are subject to market risks. The calculator provides projections based on historical averages to help with planning.
Comprehensive Guide to SIPs
Mastering Systematic Investments
Understand the core principles that make SIPs the preferred wealth creation tool for millions of investors worldwide.
A Systematic Investment Plan (SIP) is a strategy where you invest a fixed amount of money at regular intervals (usually monthly) into a mutual fund or investment vehicle.
- Discipline: It automates your savings, ensuring you invest before you spend.
- Flexibility: You can start with amounts as low as ₹500 and increase or stop anytime.
- Market Timing Eliminated: You don't need to worry about market highs or lows. You invest continuously, regardless of short-term volatility.
Compounding is when your investment earnings generate their own earnings. The longer you stay invested, the more pronounced this effect becomes.
Real-World Example
Investing ₹5,000/month at 12% expected return:
• After 10 years: Invested ₹6 Lakhs ➔ Corpus ~₹11.6 Lakhs
• After 20 years: Invested ₹12 Lakhs ➔ Corpus ~₹50 Lakhs
• After 30 years: Invested ₹18 Lakhs ➔ Corpus ~₹1.76 Crores
Notice how an extra 10 years (from year 20 to 30) added over ₹1.25 Crores, even though you only invested an additional ₹6 Lakhs!
When markets are volatile, SIPs use volatility to your advantage through Rupee Cost Averaging.
Because your investment amount is fixed, you automatically buy more mutual fund units when the market price (NAV) is low, and fewer units when the price is high. Over time, this averages out your cost per unit, protecting you from buying heavily at the top of a market cycle.
Financial planning isn't static. Our What-If Analysis feature helps you stress-test your plans.
- Scenario 1: Optimistic: What if the market returns 15%?
- Scenario 2: Conservative: What if returns are only 9%?
- Scenario 3: Accelerated: What if I increase my SIP by 10% annually?
By saving and comparing these scenarios, you can set realistic expectations and find the exact strategy needed to reach your milestones, like building an emergency fund or planning for retirement.
Frequently Asked Questions
Common questions and helpful answers about this calculator.
Disclaimer: This calculator provides estimates based on assumed rates of return. Actual returns depend on market conditions. Past performance is not indicative of future results. Investments in mutual funds are subject to market risks.