How to Calculate the Fair Value of a Stock: The DCF Method Explained Simply (with Example)

A stock’s price tells you what others are paying for it right now – not what the company is worth. If you only look at the price, you buy expensive when sentiment is good and sell cheap when it turns. The way out is an anchor of your own: the intrinsic value, often called fair value. In this guide you’ll learn the most important method behind it – discounted cash flow (DCF) analysis – including a simplified worked example, the biggest pitfalls, and why a range is more honest than any point estimate.

Fair value of a stock: what does it mean?

The fair value (intrinsic value) of a stock is what the company is worth based on its future earnings, regardless of the current share price. If the price is well below it, the stock is considered undervalued; if it’s above, expensive. Fair value is usually calculated with the DCF method: you estimate the free cash flows for the coming years, discount them back to today and divide the result by the number of shares. Because small changes in the assumptions shift the result significantly, a range is more meaningful than a single figure.

Intrinsic value: price is what you pay – value is what you get

The basic idea comes from Benjamin Graham and was popularized by Warren Buffett: a share is a stake in a business, and a business is worth all the money it generates for its owners over its remaining lifetime – discounted back to today. The share price oscillates around this value, sometimes above it for years, sometimes well below it.

This leads to the central question of any fundamental analysis: is the current price above or below the intrinsic value? That’s exactly what you need a valuation method for. The theoretically cleanest one is DCF.

The DCF logic: discounting future free cash flows

DCF stands for “discounted cash flow”. The method answers the question: what are all of the company’s future free cash inflows worth today?

To do this, you need three building blocks:

• Free cash flow (FCF): the money that’s actually left over after all operating costs and investments. It’s more honest than earnings because it’s harder to dress up through accounting choices. You can find exactly what FCF is in the glossary.
• Growth assumptions: How fast will FCF grow over the next few years – and at what rate after that “forever” (the so-called terminal growth rate)?
• Discount rate: the interest rate you use to bring future payments back to today. It reflects your required return and the company’s risk – usually 8–10% for solid companies, more like 11–14% for risky ones.

Why discount at all?

€100 in five years is worth less than €100 today. First, you could invest the money today and earn interest on it; second, every future payment is uncertain. At a 9% discount rate, €100 that only arrives in five years is worth just about €65 today (100 ÷ 1.09⁵). The further away and the riskier a payment, the less it counts today – that’s exactly what the discount rate captures.

A simplified worked example

Let’s take a fictional company with these assumptions:

• Most recent free cash flow: €100 million
• Growth: 8% per year for the next five years
• Terminal growth after that: 2% (roughly the level of inflation)
• Discount rate: 9%
• No net debt, 100 million shares outstanding

Step 1: project FCF for years 1–5 and discount each year individually.

The present values of the first five years add up to about €486 million.

Step 2: determine the terminal value. After year 5, we assume 2% terminal growth. The formula: FCF in year 6 divided by (discount rate minus terminal growth rate), i.e. 149.8 ÷ (0.09 − 0.02) ≈ €2,140 million – that’s the value of all years from year 6 onward, as seen from year 5. Discounted to today: 2,140 ÷ 1.539 ≈ €1,391 million.

Step 3: add everything up. 486 + 1,391 ≈ €1,877 million enterprise value. With 100 million shares, that corresponds to a fair value of about €18.80 per share. If the stock trades at €14, it looks cheap; at €25 it would be expensive based on these assumptions.

Notice something? About 74% of the total value sits in the terminal value – in other words, in the distant, most uncertain future. That’s the case with almost every DCF and the main reason you should never read the result as an exact number.

Small assumption, big impact: the sensitivity trap

Two small changes to our example show how sensitive the model is:

• Discount rate of 10% instead of 9%: The fair value drops from €18.80 to about €16.40 – one percentage point costs roughly 13% of the value.
• Terminal growth of 3% instead of 2%: The fair value jumps to about €21.30 – again a good 13%, this time upward.

If you combine both changes in the respective “favorable” direction, the gap between the pessimistic and the optimistic version quickly reaches 40–50% – without anything about the company having changed. That’s exactly why a DCF isn’t a result but a framework for thinking. It forces you to make your assumptions explicit – and shows you which of them really drive the value. Anyone who gives you a precise-to-the-cent “fair value” without disclosing the assumptions is selling false precision.

Multiples as a cross-check

Because DCF is so sensitive to assumptions, you should always check it against a second, simpler method: multiples. Here you compare metrics such as the P/E ratio (price-to-earnings), EV/EBIT or free cash flow yield with the company’s own history and with competitors. You’ll find a detailed overview of the most important metrics in the guide Understanding valuation metrics.

Back to the example: with earnings of €0.80 per share, our DCF value of €18.80 would correspond to a P/E ratio of about 23.5. If comparable companies trade at an average of 18 times earnings, the multiples-based value would be closer to €14.40. This discrepancy is valuable: either the company justifies a premium through higher growth or better quality – or your DCF is too optimistic. Both methods together are much more robust than either one on its own.

Why a range is more honest than a point estimate

The sensitivity analysis leads to the most important practical consequence: don’t calculate one fair value, but three scenarios – conservative, base, optimistic. In our example, that could look like this:

• Conservative (5% growth, 10% discount rate): approx. €13–14
• Base (8% growth, 9% discount rate): approx. €18–19
• Optimistic (10% growth, 8.5% discount rate): approx. €23–24

The honest statement then reads: “The stock is worth roughly €13 to €24, centered around €18.” That feels less satisfying than “exactly €18.80”, but it’s the only intellectually honest form. For the same reason, the AI report from aktienanalyse.ai deliberately provides a fair value range plus scenarios rather than a single number – you can read how to properly build bull and bear cases in the guide Bull and bear case.

Margin of safety: the buffer for your mistakes

Even a range is still an estimate. That’s why Graham added the concept of the margin of safety: only buy when the price is well below your estimated value – a discount of 20–30% is common, more for business models that are hard to forecast.

In the example: if your base value is €18.80, with a 30% margin of safety the stock only becomes really interesting below about €13. The margin isn’t a return booster but insurance against yourself: against overly optimistic growth assumptions, against the unexpected in the business, against simple calculation and reasoning errors. The wider your value range, the bigger the buffer should be.

Conclusion: how to approach it in practice

1. First understand the business model – without that, all cash flow forecasts are guesswork. The guide Learning stock analysis offers a structured introduction.
2. Build a simple DCF with deliberately cautious assumptions: realistic growth, a discount rate no lower than 8–9%, terminal growth of 2–3% at most.
3. Check the result with multiples against the company’s history and competitors.
4. Formulate a range with three scenarios instead of a point estimate.
5. Only buy with a margin of safety – and document your assumptions so you can review them later.

Once you’ve worked through this process by hand, you’ll also better understand any automated valuation – such as the fair value range that the AI analysis from aktienanalyse.ai derives from more than 35 fundamental metrics. The tool changes, the logic stays the same: value is the discounted future – and humility about your own assumptions is always part of it.

Frequently asked questions

How do you calculate the fair value of a stock?

With a DCF model: estimate future free cash flows, discount them to today using a discount rate, add a terminal value for the period after that, subtract net debt and divide by the number of shares.

Is fair value the same as analysts’ price targets?

No. Price targets are usually estimates for the next twelve months and are often based on multiples. Fair value describes the long-term intrinsic value derived from cash flows.

How reliable is a calculated fair value?

Only as good as the assumptions. Just one percentage point more growth or interest can shift the value by a fifth or more. That’s why you should work with a range and a margin of safety.

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One note from me, not part of the translation: the last FAQ answer says one percentage point can shift the value “by a fifth or more”. The article body shows about 13%. I translated it faithfully, but you may want to change the wording in the German original too.