Relative valuation is incredibly popular — and for good reason: it's quick, it's intuitive, and it mirrors how we already make decisions in everyday life. We are almost trained to think this way.
Think about the last time you bought something on eBay. You didn't try to calculate the "intrinsic value" of the item — you compared it to similar listings. You mentally adjusted for differences. If your friend is selling you a phone that costs $1,000 new, you might check what similar used phones are going for and see they're selling for $700. That immediately tells you to knock off $300. If the phone has scratches, you subtract more. If the battery needs replacing, you deduct the cost of a new battery and your time.
You started with one reference point and then normalized the price based on differences in quality. That's relative valuation. And because we do this instinctively, it feels natural to apply the same logic to businesses.
How professionals actually do relative valuation
In the professional world, this process is more structured — but at its core, it's doing the same thing.
Let's use Apple as an example.
Step 1: Choose comparable companies
The first step is to find "comparable" companies — businesses that are similar enough that comparing them makes sense.
For Apple, you might look at companies like Microsoft, Samsung, or other large technology firms. The idea is to find businesses with:
- Similar products or services
- Similar customers
- Similar growth expectations
- Similar levels of risk
Already, you can see the problem: no company is truly identical. Apple sells iPhones, laptops, services, and wearables. Microsoft sells software and cloud services. Samsung is heavily tied to hardware manufacturing. They overlap — but they are not the same.
Step 2: Pick a metric and compare it to price
Next, professionals compare price to some measure of business performance.
A common one is earnings — think of this simply as the cash a company generates after paying all the costs required to run the business.
If a company earns $10 per share and trades at $100, it has a price-to-earnings (P/E) ratio of 10. That means investors are willing to pay $10 for every $1 of earnings.
You then look at the same ratio for comparable companies.
If Apple trades at a P/E of 25, while similar companies trade at 20, you might conclude Apple is "expensive." If it trades at 15, you might think it's "cheap."
But this is where things start to get complicated.
Step 3: Identify key differences
Not all earnings are equal.
Some companies are growing faster. Some are riskier. Some generate more reliable cash flows. Some have better margins (meaning they keep more profit from each dollar of sales).
Apple, for example, has:
- A premium brand with strong customer loyalty
- High-margin services (like App Store and subscriptions)
- A massive installed base of users
Another company might rely more on low-margin hardware sales or cyclical demand.
So if Apple has higher-quality earnings, maybe it deserves a higher multiple. That means you can't just compare numbers — you have to adjust for differences.
Step 4: Break the business into pieces
Here's where professional relative valuation becomes much more detailed.
Apple isn't one business — it's several:
- iPhones
- Macs
- iPads
- Wearables
- Services
Each of these segments has different growth rates, margins, and risk profiles.
So instead of comparing Apple as a whole, analysts often:
- Break Apple into its individual business lines
- Find comparable companies or segments for each piece
- Apply the appropriate valuation multiple to each segment
For example:
- Services might be compared to software companies (higher multiples)
- Hardware might be compared to device manufacturers (lower multiples)
Step 5: Rebuild Apple's value
Once you've done that, you effectively reverse-engineer valuation.
You take:
- The earnings (or other metric) from each Apple segment
- Apply a multiple based on comparable businesses
- Add everything back together
What you end up with is a kind of "Frankenstein" valuation — a stitched-together estimate of what the market should be willing to pay for Apple based on how it prices similar businesses.
The uncomfortable truth
No two companies are ever perfectly identical. Every step in this process involves judgment:
- Which companies are truly comparable?
- Which differences matter most?
- How much should you adjust for them?
And then there's an even bigger issue.
The market moves.
The companies you used as comparables have prices that change every day. If those stocks fall, your valuation of Apple falls — even if nothing about Apple itself has changed. People will still buy iPhones. The business hasn't suddenly deteriorated.
So why did your conclusion change?
Because relative valuation doesn't actually tell you what a business is worth. It tells you what the market is currently willing to pay for similar businesses.
The core assumption — and the inconsistency
At its heart, relative valuation assumes the market is right — but only selectively.
You're implicitly saying:
- The market has correctly priced all the comparable companies
- But it has somehow mispriced the one company you're analyzing
That's the inconsistency.
If the market is efficient and rational, why would it get Apple wrong but get all of its peers right? And if the market is not efficient, why are you trusting the prices of those peers as your benchmark in the first place?
This tension sits at the center of relative valuation, even if it's rarely stated out loud.
On top of that, even companies in the same industry can have very different growth rates, risk levels, profitability, and business models. So even if the market were perfectly rational, forcing "similar" companies into the same valuation framework is already an approximation.
And markets are not always rational. History has made that clear — from the Tulip Mania to the meme-stock surge in the GameStop short squeeze.
The biggest danger
Relative valuation reflects the market's mood more than underlying reality.
- When optimism is high, multiples expand and everything looks reasonably priced
- When fear takes over, multiples collapse and everything looks cheap
Because your valuation is anchored to other companies' prices, your conclusion moves with the crowd — even if nothing about the business itself has changed.
Bottom line
Relative valuation is fast, intuitive, and natural. That's exactly why it's so popular — and so dangerous.
It doesn't anchor you to what a business is fundamentally worth. It anchors you to what everyone else is currently willing to pay.
And built into it is a quiet contradiction: trusting the market's judgment — except when it comes to the one decision you care about most.
And sometimes, the crowd is wrong.