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How to Calculate Total Addressable Market (TAM)? 

Total addressable market (TAM or total available market) represents the total revenue opportunity that’s available to a product or service if 100% market share was achieved. Calculating TAM helps understand what financing is needed for a new business line.

TAM can sometimes be expressed as the total number of companies that could become your customers.

It’s important to stress that a well-calculated TAM isn’t an accurate measure of all your future customers or revenue; it must take into account your competitors, who'll always grab a slice of the TAM pie.

But it’s a good starting point for learning how many people or companies could potentially purchase your product.

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Check out the video explainer on TAM definition, formula, and a demo of a free TAM calculator.


TAM calculations with examples

There are three ways to calculate the total addressable market. Let’s look at each method in more detail.

Three methods of calculating total addressable market.

1. Top-down market sizing 

The top-down method involves taking the total number of people in a dataset and then applying demographic and geographic filters, narrowing the results down until you reach a market subset. It is often based on existing findings from market-research firms, such as Gartner and Forrester.

Here’s an example of TAM calculation from a graduate recruitment agency in London, UK:

  • They know there are 8,900,000 people in the city.
  • They also know that 11.6% of those people are aged between 18-24.
  • By multiplying 8,900,000 by 11.6%, they estimated market size of 1,032,399.


Top-down relies on gathering macroeconomic data from third-party organizations. This type of data pre-exists and can be easily sourced from a variety of websites and institutions.


Because the data comes from third parties, it may not be entirely accurate.

The top-down method also doesn’t account for disruptive products that alter or create brand new markets due to their popularity (e.g. the Uber app dramatically increased the number of people making taxi rides per year).

2. Bottom-up market sizing

The bottom-up method is the reverse of the top-down.

To do bottom-up TAM analysis, start with a smaller market subset and then extrapolate from that until you discover a total population of buyers. A bottom-up calculation is expressed in terms of revenue.

Unlike top-down, bottom-up TAM relies on your own primary research (e.g. a survey conducted in a local market, or a pilot campaign in a small geographic area).

What is a good TAM marketing example?

For practical reasons, let’s return to the London graduate recruitment agency.

  • They sent out a campaign of email newsletters to London universities and had 25,000 sign-ups.
  • They charge a single fixed fee of £100 per person recruited.
  • 25,000 x £100 = a total potential revenue of £2,500,000.

The simple TAM formula in this case is:

(# of possible Accounts) x (Annual Contract Value) = TAM

How to calculate tam


Bottom-up TAM is based on your own data generated in-house. Therefore the final calculation is more likely to be accurate and relevant to your business.


Due to the assumptions being made from a small subset of data, the ultimate TAM calculation derived from the bottom-up technique can be misleading.

This is particularly pertinent if you’re trying to make a global TAM calculation, where factors such as population density, economic prosperity and consumer habits can vary from country to country.

However, we recommend this as the best method for most B2B SaaS companies.

3. Value-theory market size

The value-theory method begins by asking what a buyer would be willing to pay for a product or service, based on the value it delivers.

You then multiply this by the total number of people or companies that perceive the same value and would be willing to adopt your solution in place of the competition. Here are some things you want to know to determine the total available market using this method:

  • How many people would get value out of your latest idea?
  • How much they would be willing to pay for it?


Value theory is useful for companies that have developed a unique product that is creating new markets or reshaping current ones.

It’s a good method for companies that don’t have any market data at their disposal or don’t have the resources to conduct their own research (typically startups).

It’s also beneficial if you’re testing new features or upgrades to existing products.


Value theory is largely based on conjecture and guesswork; its conclusions will never be 100% accurate.

But, by focusing on the value your product can deliver to consumers, you can estimate how to capture that value through pricing.

4. Use Cognism's TAM calculator

As you scroll down the page, you'll realize calculating your TAM is tough.

So we decided to make it a whole lot easier with our TAM calculator.

The TAM template offers you enough Cognism functionality to help you work out the size and makeup of your total addressable market. Cool right? 😎

Why is TAM analysis important?

Analyzing your TAM is key to estimating how many potential customers are out there and predicting how fast your business may grow. It helps you decide if it's worth investing in a new product or service.

It also gives you a top-down overview of your target market and helps segment your audience into different groups.

It assists you in identifying which types of customers would be most receptive to your offering. After you define TAM, you can allocate resources accordingly. It gives you a good idea of where you can expect the best return on your investment.

Why is total addressable market useful for B2B and SaaS?

In this industry, sales cycles are often longer and deal sizes are larger. Therefore, knowing who your ideal customers are, and how many of them there are, can make a real difference to your company’s growth.

Investors also look for well-thought-out TAM calculations.

If you can prove that you have a good understanding of the market and your product’s place in it, then investors will be much more likely to buy into your company.

What are the benefits of finding your TAM?

Calculating the total addressable market is the crucial first step in developing a winning sales strategy. It can deliver many positive benefits to your business. The top 6 benefits of the total addressable market are:

  • Identifying new revenue opportunities
  • Calculating your potential revenue
  • Finding investors
  • Planning your outreach
  • Generating B2B leads
  • Setting achievable goals

What is TAM and its benefits for B2Bs.

What are the differences between TAM, SAM, and SOM?

People often speak about TAM alongside SAM and SOM. 

Acronym overload, right? 

So let’s break each one of them down so we know exactly what we’re talking about. 

  • SAM is Serviceable Available Market. It is the segment of TAM your products and services target.
  • SOM is a Serviceable Obtainable Market. It is the segment of your SAM you can realistically capture

How calculating total addressable market helped Cognism?

Like many successful start-ups, Cognism’s growth strategy all started with a total addressable market. By thoroughly investigating and defining our buying audience, we were able to develop innovative products and winning go-to-market strategies.

We adhere to the bottom-up TAM method. Here's the workflow you can use to find your total addressable market:

  1. Ask customer service to analyze your existing customer base and look for trends.
  2. Investigate other geographic or industry sectors based on those trends.
  3. Use the information to define an accurate buyer persona.
  4. Run a search in Cognism Prospector to discover prospects who match your persona.

You can now reach out to them!

Five-step guide to finding out your total addressable market with Prospector tool.

Our flagship tool, Prospector, is ideal for generating an accurate bottom-up TAM representation. But don't take our word for it. This is what Tom Andrews, Revenue Operations Manager at PassFort, had to say about enriching their leads database with Cognism's Prospector:

"[Cognism] gave us an understanding of the market and how many potential buyers were out there. It helped us to discover our Total Addressable Market. It’s a good market research tool, as well as a prospecting tool."

As a result, they found 450 new potential customers in target accounts. you can read full case study here.

Key takeaways

  • If you don’t know your TAM,  you don’t know how fast your business may grow.
  • Investors are more likely to buy into your company if you have a well-thought-out TAM.
  • Cognism recommends using the bottom-up TAM method.
  • Cognism’s B2B data solutions are tailor-made for accurate TAM analysis.
We’d love to show you what our pioneering prospecting tech can do. Click 👇 to schedule a demo with our TAM experts.

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