WACC Calculator

Calculate your company's weighted average cost of capital in seconds. Enter cost of equity, debt, tax rate, and capital amounts to find your WACC hurdle rate for investment decisions.

If you've ever wondered whether that new project, acquisition, or expansion is actually worth pursuing, your WACC holds the answer. This calculator takes the complexity out of one of corporate finance's most important metrics and gives you a clear number to work with.

Enter your cost of equity, cost of debt, capital amounts, and tax rate—and you'll instantly see the minimum return your investments need to generate. Anything above this number creates real value for your business. Anything below it? That's value walking out the door, even if the project looks profitable on the surface.

Whether you're a CFO stress-testing a major capital decision, a business owner weighing expansion options, or a finance student trying to make sense of valuation models, this tool gives you the clarity you need to move forward with confidence.

What is WACC, Really?

WACC—Weighted Average Cost of Capital—sounds technical, but the concept is surprisingly intuitive once you see it in action.

Your company needs money to operate and grow. That money comes from two main sources: shareholders (equity) and lenders (debt). Here's the thing—neither group is giving you money for free. Shareholders expect returns for taking on risk. Lenders expect interest payments for letting you use their capital.

WACC blends these costs together based on your capital structure. If you're 70% equity-financed and 30% debt-financed, your WACC weights each cost accordingly. The result is a single percentage that represents your overall cost of capital.

Why does blending matter? Because it's not enough to know your loan rate or your shareholders' expectations in isolation. You need the full picture to make smart decisions about where to invest your company's resources.

Why Your WACC Number Actually Matters

Here's where WACC stops being an academic exercise and starts being genuinely useful.

It's your investment filter. Every project, acquisition, or expansion your company considers should clear this hurdle. A 15% return on a new product line sounds fantastic—until you realize your WACC is 16%. That project would actually destroy value, not create it. Without knowing your WACC, you're flying blind on capital allocation.

It drives company valuation. When investors or acquirers value your business, they discount your future cash flows back to present value. The discount rate? Your WACC. A company with a 7% WACC is worth significantly more than an identical company with a 12% WACC—same cash flows, very different valuations.

It reveals capital structure opportunities. Your WACC isn't fixed. It changes based on how you finance your business. Many companies discover they can lower their WACC (and raise their valuation) by optimizing their debt-to-equity mix. This calculator helps you model those scenarios.

A real example: A mid-sized manufacturing company was evaluating a $5 million equipment upgrade expected to generate $600,000 in annual savings—a 12% return. Looked great on paper. But their WACC analysis revealed a 13.2% cost of capital. That "profitable" investment would have actually eroded shareholder value by about $50,000 annually. They passed on the project and allocated the capital elsewhere. That's WACC doing its job.

The WACC Formula: Breaking It Down

The formula looks intimidating at first glance, but each piece has a clear purpose:

WACC = (E/V × Re) + (D/V × Rd × (1 - Tc))

Let's translate:

Component

What It Means

Why It's There

E/V

Equity weight (equity ÷ total capital)

How much of your funding comes from shareholders

Re

Cost of equity

What shareholders expect to earn

D/V

Debt weight (debt ÷ total capital)

How much of your funding comes from lenders

Rd

Cost of debt

Your interest rate on borrowings

(1 - Tc)

Tax shield multiplier

Adjusts for the tax benefit of interest deductions

The tax shield is the secret sauce. Interest payments reduce your taxable income, so the government effectively subsidizes part of your debt cost. If you pay 8% interest and your tax rate is 25%, your true after-tax cost of debt is only 6%. This is why adding some debt (up to a point) typically lowers your overall WACC.

How to Use This Calculator

Step 1: Enter your cost of equity This is what your shareholders expect to earn. Don't guess—use the CAPM method below or comparable company data. Most established companies fall between 8% and 15%.

Step 2: Enter your equity amount For public companies, use market capitalization (share price × shares outstanding). For private companies, use your most recent valuation. If you don't have one, book equity works as a starting point, but know it's likely understated.

Step 3: Enter your cost of debt Your weighted average interest rate across all borrowings. Check your loan agreements—it's the rate you're actually paying, not the prime rate or some benchmark.

Step 4: Enter your debt amount Include everything that charges interest: term loans, lines of credit, bonds, equipment financing. Leave out accounts payable and accrued expenses—those don't have an explicit interest cost.

Step 5: Enter your corporate tax rate Use your effective rate (taxes actually paid ÷ pre-tax income) from recent financials. It's usually lower than the statutory rate due to deductions and credits.

Step 6: Review your WACC The calculator shows your weighted average cost of capital instantly. This is your hurdle rate for investment decisions.

Finding Your Inputs: The Practical Guide

This is where most people get stuck. Let's fix that.

How to Calculate Your Cost of Equity

The Capital Asset Pricing Model (CAPM) is the standard approach:

Cost of Equity = Risk-Free Rate + (Beta × Market Risk Premium)

Here's how to find each piece:

Risk-free rate: Use the current 10-year U.S. Treasury yield. As of 2024-2025, this typically runs between 4% and 5%. You can find today's rate on the Treasury Department website or any financial news site.

Beta: This measures how volatile your stock is compared to the overall market. A beta of 1.0 means you move with the market. Higher than 1.0 means more volatile; lower means more stable.

  • Public companies: Look up your beta on Yahoo Finance, Google Finance, or Bloomberg. It's listed right on the stock summary page.
  • Private companies: Find 3-5 public companies in your industry and average their betas. Then adjust upward slightly (private companies are typically riskier due to less liquidity).

Market risk premium: This is the extra return investors expect for investing in stocks versus risk-free bonds. The historical average is around 5-6%. Most analysts use 5.5%.

Putting it together: If the risk-free rate is 4.5%, your beta is 1.2, and you use a 5.5% market risk premium:

Cost of Equity = 4.5% + (1.2 × 5.5%) = 4.5% + 6.6% = 11.1%

How to Calculate Your Cost of Debt

If you have one loan, this is easy—it's your interest rate.

If you have multiple debt instruments (and most companies do), calculate a weighted average:

Debt Type

Amount

Rate

Weight

Weighted Rate

Bank term loan

$2,000,000

6.5%

57%

3.71%

Equipment financing

$800,000

7.2%

23%

1.66%

Line of credit

$700,000

8.0%

20%

1.60%

Total

$3,500,000


100%

6.97%

Your cost of debt is 6.97%. The calculator will apply the tax shield automatically.

Pro tip: If you're evaluating a future capital structure (like taking on new debt), use the rate you'd pay on new borrowings, not your existing average.

WACC Benchmarks: How Do You Compare?

WACC varies dramatically by industry. A "good" WACC for a utility company would be disastrous for a biotech startup. Here's what typical ranges look like:

Industry

Typical WACC

Why

Utilities

5% - 7%

Stable regulated cash flows, heavy debt capacity

Real Estate (REITs)

6% - 8%

Tangible assets, predictable income, favorable debt terms

Consumer Staples

7% - 9%

Steady demand, established brands, moderate leverage

Healthcare

8% - 10%

Mix of stable (pharma) and volatile (biotech) segments

Industrials/Manufacturing

8% - 11%

Cyclical demand, significant capital requirements

Consumer Discretionary

9% - 12%

Economic sensitivity, varying brand strength

Technology

10% - 14%

High growth expectations, often equity-heavy

Biotechnology

12% - 18%

High failure rates, R&D intensity, minimal debt

Early-stage Startups

20% - 40%+

Maximum uncertainty, no track record, all equity

What this means for you: If your WACC is significantly higher than your industry average, you may be overleveraged, paying too much for capital, or perceived as riskier than peers. If it's lower, you might have room to take on more risk or invest more aggressively.

Real-World Examples

Example 1: Growing SaaS Company

Situation: CloudTech Inc. is a B2B software company considering a $3M product expansion. They need to know their hurdle rate.

Their numbers:

  • Cost of equity: 13% (higher beta due to growth stock characteristics)
  • Equity market value: $18 million
  • Cost of debt: 7%
  • Debt: $4 million (a small term loan)
  • Tax rate: 21%

Calculation:

  • Total capital: $22 million
  • Equity weight: 81.8% | Debt weight: 18.2%
  • WACC = (81.8% × 13%) + (18.2% × 7% × 0.79)
  • WACC = 10.63% + 1.01% = 11.64%

Decision: Their product expansion projects 18% returns. At 11.64% WACC, this clears the hurdle comfortably. Green light.

Example 2: Established Manufacturing Firm

Situation: Precision Parts Corp. is evaluating whether to modernize their factory floor. The CFO wants to ensure the investment makes financial sense.

Their numbers:

  • Cost of equity: 10% (stable, mature business)
  • Equity market value: $25 million
  • Cost of debt: 5.5%
  • Debt: $35 million (significant but manageable leverage)
  • Tax rate: 24%

Calculation:

  • Total capital: $60 million
  • Equity weight: 41.7% | Debt weight: 58.3%
  • WACC = (41.7% × 10%) + (58.3% × 5.5% × 0.76)
  • WACC = 4.17% + 2.44% = 6.61%

Decision: Their factory modernization projects 9% returns. At 6.61% WACC, this creates significant value. The $12M investment is approved.

Example 3: Retail Chain Expansion

Situation: FreshMart is considering opening 5 new locations. Each store costs $800K and projects $90K annual profit—an 11.25% return. Worth it?

Their numbers:

  • Cost of equity: 12%
  • Equity market value: $12 million
  • Cost of debt: 6.5%
  • Debt: $8 million
  • Tax rate: 22%

Calculation:

  • Total capital: $20 million
  • Equity weight: 60% | Debt weight: 40%
  • WACC = (60% × 12%) + (40% × 6.5% × 0.78)
  • WACC = 7.2% + 2.03% = 9.23%

Decision: Store expansion at 11.25% return exceeds the 9.23% WACC by nearly 2 percentage points. Each store creates roughly $16,000 in annual value above the cost of capital. Expansion approved.

Common Mistakes (And How to Avoid Them)

Mistake #1: Using book value instead of market value Book value is backward-looking—it tells you what shareholders invested historically, not what the company is worth today. A successful company's market value often exceeds book value by 3-5x or more. Using book value dramatically understates equity weight and distorts your WACC.

Fix it: For public companies, always use market cap. For private companies, use a recent valuation or comparable transaction.

Mistake #2: Forgetting the tax shield Skipping the (1 - Tc) multiplier makes debt look more expensive than it really is. This leads to overstated WACC and rejected projects that would have created value.

Fix it: Always apply the tax adjustment to your cost of debt. This calculator handles it automatically.

Mistake #3: Using the "gut feel" cost of equity Picking 12% because it "seems reasonable" isn't analysis—it's guessing. Your cost of equity should be calculated systematically.

Fix it: Use CAPM with actual data. Find your beta, use current Treasury rates, and apply a consistent market risk premium.

Mistake #4: Including non-interest-bearing liabilities Accounts payable, accrued wages, and deferred revenue aren't debt in the WACC sense. They don't have an explicit interest cost and shouldn't be in your calculation.

Fix it: Only include debt that charges interest: loans, bonds, credit facilities, equipment financing.

Mistake #5: Setting and forgetting Your WACC changes as interest rates move, your stock price fluctuates, and you add or pay down debt. A WACC calculated two years ago may be significantly off today.

Fix it: Recalculate at least annually, and any time you make major financing changes.

Frequently Asked Questions

What is a good WACC percentage?

"Good" depends entirely on context. A 6% WACC is excellent for a utility company but would signal serious problems for a tech startup (investors would expect much higher returns for that risk). Generally, established companies in stable industries see WACCs between 6-10%. Growth companies and riskier businesses typically range from 10-15% or higher. Compare your WACC to industry peers rather than looking for a universal benchmark.

How do I calculate cost of equity if my company isn't public?

Use the CAPM formula with a proxy beta. Find 3-5 public companies that match your business model, industry, and size as closely as possible. Average their betas, then add a small premium (1-3 percentage points) for illiquidity and company-specific risk. Private company cost of equity is typically 2-4% higher than comparable public companies.

Should I use book value or market value for debt?

For most companies, book value of debt is fine—it's usually close to market value unless you've had dramatic interest rate changes since borrowing or your credit quality has shifted significantly. If you have publicly traded bonds, you can use their current market price. For standard bank loans, book value works.

Why does adding debt sometimes lower WACC?

Two reasons. First, lenders accept lower returns than shareholders because they get paid first in bankruptcy—they're taking less risk. Second, the tax deductibility of interest creates a government subsidy on your borrowing costs. So up to a point, replacing expensive equity with cheaper after-tax debt reduces your blended cost of capital. But there's a limit—too much debt increases bankruptcy risk, scares off investors, and eventually pushes WACC back up.

How often should I update my WACC?

At minimum, once per year during your planning cycle. Also recalculate after major financing events (new loans, equity raises, debt payoffs), significant stock price movements (up or down 20%+), or meaningful interest rate shifts. For active M&A or capital allocation work, use a fresh WACC for each analysis.

What's the relationship between WACC and discount rate?

WACC is a discount rate—specifically, the one you use to evaluate projects with similar risk to your overall company. For most corporate investment decisions, WACC and discount rate are interchangeable. However, if you're evaluating a project that's significantly riskier or safer than your core business, you should adjust the discount rate accordingly. A conservative expansion deserves a lower rate; a speculative R&D bet deserves a higher one.

Can my WACC ever be too low?

Technically, lower WACC is better—it means cheaper capital and higher company valuations. But an unusually low WACC might signal that you're being too aggressive with assumptions (understated cost of equity, for example) or that you're overleveraged. Very high debt loads can produce artificially low WACCs that don't account for increased bankruptcy risk. Always sanity-check your result against industry benchmarks.

How do I find the cost of debt for a company with no current borrowings?

Look at what rate you would pay if you borrowed. Check rates for comparable companies, ask your banker for indicative terms, or use yields on corporate bonds for your credit rating and industry. You can also add a spread (typically 1-3%) over the risk-free rate based on your company's creditworthiness.

Why is interest tax-deductible but dividends aren't?

This is a quirk of tax law that significantly affects capital structure decisions. Interest payments are considered a business expense and reduce taxable income. Dividends are paid from after-tax profits and provide no tax benefit. This asymmetry makes debt financing more attractive from a pure cost perspective, which is why the tax shield appears in the WACC formula.

What if my WACC calculation seems way off from expectations?

Double-check your inputs systematically. The most common errors: using book value instead of market value for equity, forgetting the tax shield on debt, using an outdated beta, or including non-interest-bearing liabilities in debt. Compare your result to the industry benchmarks above. If you're still getting strange numbers, walk through the CAPM calculation step-by-step—that's usually where errors hide.