Contents
- 1 NPV Calculator — Net Present Value of Cash Flows
NPV Calculator — Net Present Value of Cash Flows
Calculate Net Present Value of any investment or project. Discount future cash flows to today and decide whether to invest.
What is NPV?
Net Present Value (NPV) is the cornerstone of corporate finance and project evaluation. It tells you whether a proposed investment will create wealth (positive NPV) or destroy value (negative NPV) after accounting for the time value of money. Used by CFOs, project managers, investors, and analysts to decide whether to commit capital to a project, acquisition, or asset purchase.
The NPV Formula
NPV = -Initial Investment + Σ [Cash Flowt / (1+r)t] Where:
- Initial Investment: Upfront outflow at time 0
- Cash Flowt: Net cash flow in year t
- r: Discount rate (cost of capital, hurdle rate, or required return)
- t: Time period (years)
NPV Decision Rule
| NPV Result | Decision | Interpretation |
|---|---|---|
| NPV > 0 | ACCEPT | Project creates value; expected return exceeds cost of capital |
| NPV = 0 | INDIFFERENT | Project just meets required return; consider strategic factors |
| NPV < 0 | REJECT | Project destroys value; better to invest elsewhere at hurdle rate |
For mutually exclusive projects (can only pick one), choose the project with the HIGHEST positive NPV.
Why Time Value of Money Matters
A rupee today is worth more than a rupee tomorrow because:
- Opportunity cost: Today’s rupee can be invested to earn returns
- Inflation: Tomorrow’s rupee buys less due to rising prices
- Risk: Future cash flows are uncertain — there’s risk of non-receipt
- Liquidity preference: Most people prefer money now over later
Example: ₹1 Lakh Now vs ₹1 Lakh in 5 Years
At 10% discount rate, ₹1,00,000 received in 5 years is worth only ₹62,092 today. So if someone offers you “₹1L in 5 years” vs “₹70K today” — take today’s ₹70K, because it’s worth more (₹70K > PV of ₹62K).
Choosing the Right Discount Rate
| Context | Typical Discount Rate | Basis |
|---|---|---|
| Personal finance (low risk) | 6-8% | Risk-free rate (G-Sec yield) |
| Personal finance (moderate risk) | 10-12% | Equity expected return |
| Listed corporate (low risk) | 10-13% | WACC (Weighted Avg Cost of Capital) |
| Listed corporate (high risk) | 14-18% | WACC + risk premium |
| Startup / Early stage | 20-30% | VC required return |
| Real estate project | 14-16% | Hurdle rate |
| Infrastructure project | 10-14% | Sovereign-backed return + premium |
WACC formula (corporate): WACC = (E/V × Re) + (D/V × Rd × (1−T)) where E = equity, D = debt, V = E+D, Re = cost of equity, Rd = cost of debt, T = tax rate.
Worked Example — Cold Storage Project
A food processing company evaluates a ₹10 lakh investment in cold storage equipment. Expected annual savings over 5 years: ₹3L, ₹3.5L, ₹4L, ₹2.5L, ₹2L. Discount rate = 10%.
| Year | Cash Flow (₹) | Discount Factor | Present Value (₹) |
|---|---|---|---|
| 0 | (10,00,000) | 1.0000 | (10,00,000) |
| 1 | 3,00,000 | 0.9091 | 2,72,727 |
| 2 | 3,50,000 | 0.8264 | 2,89,256 |
| 3 | 4,00,000 | 0.7513 | 3,00,526 |
| 4 | 2,50,000 | 0.6830 | 1,70,753 |
| 5 | 2,00,000 | 0.6209 | 1,24,184 |
| NPV | 1,57,446 | ||
Decision: ACCEPT (NPV positive). The project will add ₹1.57 lakh of value beyond the required 10% return.
NPV vs IRR — Which One Wins?
| Aspect | NPV | IRR |
|---|---|---|
| Output Unit | Rupees (₹) | Percentage (%) |
| Reinvestment Assumption | At discount rate (realistic) | At IRR (unrealistic if IRR > cost of capital) |
| Multiple IRRs | Single value | Possible if cash flows change sign multiple times |
| Scale Sensitivity | Reflects project size | Same IRR for ₹1L and ₹100Cr — misleading |
| Mutually Exclusive Projects | Preferred | Can mislead — choose based on NPV |
| Practical Usage | CFO favored | Operations & equity investor favored |
Best practice: Use NPV for decision-making, IRR for communication. Both should agree on accept/reject for conventional cash flows. For unconventional cash flows (e.g., mining projects with closure costs), trust NPV.
Common NPV Pitfalls
- Wrong discount rate: Using risk-free rate for risky projects overstates NPV; using too-high rate rejects good projects
- Ignoring inflation: Either keep all cash flows in real terms with real discount rate, OR all in nominal terms with nominal rate — don’t mix
- Forgetting working capital: Project requires WC investment year 0; recovered at end. Both must be in cash flows.
- Treating sunk costs: Past expenses already incurred are irrelevant — only incremental cash flows matter
- Ignoring opportunity cost: Using your own land/equipment “free” understates cost — include rent/depreciation foregone
- Missing terminal value: For long-term projects, salvage value or perpetuity value at end can be significant
- Tax treatment errors: Cash flows should be POST-tax; include depreciation tax shield correctly
NPV in Personal Finance
NPV isn’t just for corporates — it’s powerful for personal decisions too:
- Buy vs Rent: Compare NPV of homeownership cash flows (down payment, EMI, maintenance, appreciation) vs renting + investing the difference
- EV vs Petrol Car: Compare NPV of (purchase price differential) vs (fuel + maintenance savings) over ownership period
- Solar Rooftop: ₹2-3L investment vs 25-year electricity savings — almost always positive NPV in India given subsidies + rising power tariffs
- MBA / Higher Education: NPV of (tuition cost + foregone salary) vs (post-MBA salary uplift over career)
- Insurance Decision: NPV of premiums paid vs expected claims (mostly negative for low-risk individuals = pure protection)
Frequently Asked Questions
What’s the difference between NPV and Profitability Index?
NPV = PV of inflows − Initial Investment (absolute rupee value). PI = PV of inflows / Initial Investment (ratio). NPV tells you total wealth created; PI tells you wealth per rupee invested. For ranking projects with limited capital, use PI. For absolute decisions, use NPV.
Can NPV be negative even with positive cash flows?
Yes — if the future cash flows are insufficient to recover the initial investment at the required return. A project that gives ₹3L over 5 years on ₹10L investment is unprofitable at any reasonable discount rate, even though gross cash flows are positive.
What discount rate should I use for personal financial planning?
For comparison with PPF/FD: use 7-8% (post-tax equivalent). For comparison with equity: use 11-12%. For accounting for inflation only: use 5-6%. Choose based on what you’d actually do with the money if you didn’t take this opportunity.
How does NPV handle inflation?
Two consistent approaches: (1) Nominal cash flows discounted at nominal rate (most common), OR (2) Real cash flows (inflation-adjusted) discounted at real rate. Either works; mixing them is the most common error in NPV analysis.
What if a project’s cash flows are uncertain?
Use sensitivity analysis (vary discount rate, cash flows) or scenario analysis (best/base/worst). Monte Carlo simulation gives a probability distribution of NPV. Some analysts use risk-adjusted discount rates (higher for risky projects); others use certainty equivalents.
Does NPV consider taxes?
Yes — cash flows should be POST-TAX. Include depreciation tax shield (Tax Saved = Depreciation × Tax Rate). Initial investment is pre-tax (you pay the full amount); operating cash flows are post-tax. Salvage value at end requires capital gains tax adjustment.
What is “Modified NPV” or MIRR?
MIRR (Modified IRR) addresses IRR’s reinvestment assumption by explicitly assuming intermediate cash flows are reinvested at the cost of capital (not at IRR). It bridges NPV and IRR — more realistic than IRR alone. NPV doesn’t have a “modified” version because its reinvestment assumption is already realistic.
How is NPV used in M&A?
Acquirers compute NPV of acquired company’s future cash flows; if NPV > offer price, deal is value-accretive. Discount rate is typically the acquirer’s WACC adjusted for target’s risk. Terminal value (perpetuity growth model) is critical and often 70-90% of total enterprise value.
Is higher NPV always better?
For unconstrained capital: Yes, accept all positive NPV projects. For constrained capital: Rank by PI or use capital rationing. For mutually exclusive projects of different sizes/lives: equivalent annual annuity (EAA) method or replacement chain analysis is more accurate.
How does inflation affect the discount rate?
Nominal rate = Real rate + Inflation + (Real × Inflation). E.g., 4% real + 6% inflation ≈ 10.24% nominal. For long-term projects, getting inflation expectation right is critical. Underestimating inflation rejects worthwhile projects; overestimating accepts bad ones.