IRR and NPV Calculator for Investment Projects
Calculate IRR (Internal Rate of Return) and NPV (Net Present Value) for any investment. Enter initial outlay, annual cash flow, and discount rate — get an instant verdict on whether the project beats your opportunity cost.
- Data verified · June 2026
- Edited by Martín Rodríguez
- Formula verified by automated tests
- Private — runs on your device
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How to use this calculator
Follow this tool’s steps, then review its formula, assumptions, and limits below.
When to use this calculator
- Decide whether rental income from an apartment beats a sovereign bond.
- Your company analyzes expansion to a new city with CapEx of $50M.
- You're deciding between buying a franchise or investing in a diversified portfolio.
- Compare two industrial machines with different costs and useful lives.
- Evaluate crypto staking or liquidity pools against a fixed-income alternative.
Typical Discount Rates by Investor Type (2026)
| Source / Context | Approx. Rate (2026) | When to Use |
|---|---|---|
| US Savings Account | 4–5% | Low-risk personal decisions |
| US Treasury 10Y (risk-free) | 4–5% USD | Risk-free baseline |
| S&P 500 Historical Average | ~10% nominal | Equity opportunity cost |
| Real Estate | 6–10% | Rental property analysis |
| WACC – US Large Cap | 8–12% | Corporate projects (CapEx, expansion) |
| WACC – SME | 12–20% | Smaller company projects |
| VC / Startup Hurdle | 25–40% | High-risk ventures |
| Risk Premium Add-on (new ventures) | 5–15 pp above baseline | Innovation or high-uncertainty projects |
Fuente: Damodaran Online – Valuation Data; CFA Institute – Capital Budgeting (2026)
How it works
What are NPV and IRR
They are the two classic indicators for project evaluation, found in every corporate finance textbook (Brealey-Myers, Ross, Damodaran).
Net Present Value (NPV)
The sum of discounted future cash flows in today's dollars, minus the initial investment:
NPV = −Investment + Σ (Cash Flow_t / (1+r)^t) for t = 1 to nInternal Rate of Return (IRR)
The discount rate r* that makes NPV = 0. Represents the project's effective return rate.
0 = −Investment + Σ (Cash Flow_t / (1+r*)^t)No closed-form solution — calculated iteratively (bisection or Newton-Raphson).
Payback Period
Years needed to recover the investment without discounting. Useful but secondary — ignores time value of money.
Simple payback = Investment / Annual cash flowDecision Table
| NPV | IRR vs Discount Rate | Decision |
|---|---|---|
| > 0 | IRR > r | ACCEPT (aligned signals) |
| = 0 | IRR = r | Indifferent |
| < 0 | IRR < r | REJECT (aligned signals) |
| > 0 | IRR < r | Rare — complex flows, trust NPV |
| < 0 | IRR > r | Rare — complex flows, trust NPV |
NPV Reference Table
Example: $100 invested, $20/year constant cash flow (IRR of this project = 15%):
| Project years | Rate 5% | Rate 10% | Rate 15% | Rate 20% | Rate 30% |
|---|---|---|---|---|---|
| 5 years | −$13.2 | −$24.2 | −$32.9 | −$40.2 | −$52.9 |
| 10 years | +$54.4 | +$22.9 | −$0.4 | −$16.1 | −$39.5 |
| 15 years | +$107.1 | +$52.1 | +$17.3 | −$4.9 | −$32.1 |
| 20 years | +$149.3 | +$70.1 | +$25.6 | −$0.6 | −$28.5 |
When rate = IRR (15%), NPV hovers near zero at long horizons.
Typical Discount Rates
| Source | Rate (approx 2026) | When to use |
|---|---|---|
| US savings account | 4-5% | Low-risk personal decisions |
| US Treasury 10Y | 4-5% USD | Risk-free baseline |
| S&P 500 historical avg | ~10% nominal | Equity opportunity cost |
| VC / startup hurdle | 25-40% | High-risk ventures |
| Real estate | 6-10% | Rental property analysis |
| WACC (US large cap) | 8-12% | Corporate projects |
| WACC (SME) | 12-20% | Smaller companies |
For high-risk projects (new venture, innovation), add a risk premium of 5-15 percentage points above your baseline.
Example 1: Apartment Rental
Scenario: Buy apartment for USD 100,000. Rents for USD 500/month = USD 6,000/year. Hold 10 years, sell for USD 110,000.
Initial investment: −USD 100,000
Cash flows (years 1-9): USD 6,000
Cash flow (year 10): USD 6,000 + USD 110,000 = USD 116,000
Discount rate: 7% USD
NPV ≈ −$1,966 USD (slightly negative)
IRR ≈ 6.7% USDVerdict: returns less than a 7% bond (not financially compelling, though property has emotional value, inflation hedge, etc.).
Example 2: Franchise
Scenario: Cafe franchise. Initial investment $50,000. Net cash flow $15,000/year for 5 years. Discount rate 20%.
NPV = −50,000 + 15,000 × [1 − 1.20^(−5)] / 0.20
= −50,000 + 15,000 × 2.991
= −50,000 + 44,860
= −$5,140 (negative NPV)
IRR ≈ 15.2% (below 20%)Verdict: Not worth it at 20% hurdle rate. Becomes worthwhile only if your discount rate falls below ~15.2%.
NPV and IRR with Variable Cash Flows
This calculator assumes constant annual cash flow. For variable flows, use Excel or Google Sheets:
=NPV(rate; cash_flows) — note this is a present-value-of-future-flows function; subtract the initial investment separately=IRR(cash_flows) — first row must be the negative initial investmentWhy IRR Can Mislead
1. Different project scales: High IRR on a small project does not beat lower IRR on a large one. NPV wins.
2. Multiple IRRs: If cash flows flip signs multiple times, multiple IRRs exist. Trust NPV only.
3. Reinvestment assumption: IRR assumes reinvesting intermediate cash flows at the same rate — often unrealistic at high IRRs. Modified IRR (MIRR) corrects this.
4. Mutually exclusive projects: If choosing between A and B, pick highest NPV, not highest IRR.
Discounted Payback
| Year | Cash Flow | Present Value (10%) | Cumulative |
|---|---|---|---|
| 0 | −100,000 | −100,000 | −100,000 |
| 1 | 25,000 | 22,727 | −77,273 |
| 2 | 25,000 | 20,661 | −56,611 |
| 3 | 25,000 | 18,783 | −37,828 |
| 4 | 25,000 | 17,075 | −20,753 |
| 5 | 25,000 | 15,523 | −5,230 |
| 6 | 25,000 | 14,112 | +8,882 |
Discounted payback: just over 5 years (at 10% rate).
Simple payback: 4.0 years.
WACC — Corporate Discount Rate
WACC = (E/V × Re) + (D/V × Rd × (1 − T))Where:
CAPM: Re = Rf + β × (Rm − Rf)
Common Mistakes in NPV/IRR Analysis
1. Wrong currency: USD cash flows → USD rate. Inflation-adjusted flows → real rate.
2. Ignoring taxes: Always use after-tax cash flows.
3. Missing salvage value: Add terminal asset sale to final year cash flow.
4. Ignoring working capital: Upfront investment in inventory/receivables is a real cash outflow.
5. Overestimating cash flows: Run pessimistic/base/optimistic scenarios.
6. Comparing different time horizons: Use equivalent annual NPV for fair comparison.
Related Calculators
Example: $100K investment, $25K annual cash flow for 6 years, 10% discount rate
−Investment + Σ Cash Flow / (1+r)^t.−100,000 + 25,000/(1.10)¹ + 25,000/(1.10)² + ... + 25,000/(1.10)⁶.−100,000 + 108,882 = +$8,882 (positive).100,000 / 25,000 = 4.0 years.Frequently asked questions
What is IRR and how do you calculate it?
=IRR(cash_flows) where the first value is the negative initial investment.What is NPV and when is it positive?
NPV = −Investment + Σ CashFlow/(1+r)^t. NPV > 0: the project creates more wealth than your best alternative — accept. NPV = 0: breakeven with your opportunity cost. NPV < 0: destroys value — reject. NPV depends heavily on the chosen discount rate.What discount rate should I use?
What is the difference between NPV and IRR?
Why is my IRR negative or very high?
How do I handle uneven cash flows?
=NPV(rate; flows) plus =IRR(flows) with actual year-by-year values; (3) for flows growing at a constant rate, use the Gordon model: NPV = F / (r − g). Always add salvage value as the final-period cash flow.Is a small positive NPV enough to justify the investment?
Can a project have high IRR but low NPV?
How do I include taxes in the analysis?
How do I compare projects with different time horizons?
Sources & references
Methodology & trust
Finance calculator with its formula verified automatically against Ross, Westerfield, Jaffe — Corporate Finance (Chapter NPV/IRR), per our editorial policy and methodology.
Updated: June 2026. Parameters are verified periodically against the cited sources.
Calculations run 100% in your browser. We do not store or transmit your data.
Indicative results. For critical decisions, consult a professional.
Rodríguez, M. (2026). IRR and NPV Calculator for Investment Projects. Hacé Cuentas. https://hacecuentas.com/en/tir-van-inversion
Content licensed under CC-BY 4.0 — reuse it citing the source with a link to Hacé Cuentas.