Skip to Main Content


This guide supports UCI’s innovation and entrepreneurship community by connecting users to relevant resources used to conduct research.

Email this link:

Market Size & Share

  • For market size, select the At a Glance section in a report.
  • For market share, select the Companies section in a report.
  • Market Analysis (left menu) > Market Size Estimates

There are a zillion vendors selling reports about every product or industry imaginable, and the UCI Libraries cannot possibly buy all of them. Even if you can't afford to buy a report, there's no rule stopping you from citing content in a vendor's free preview!

Diagram of concentric circles showing TAM as the largest circle, SAM as the middle circle, and SOM as the smallest circle.


The TAM - SAM - SOM Model is a useful method of estimating your market size.

  • TAM: Total Attainable Market
  • SAM: Serviceable Available Market
  • SOM: Serviceable Obtainable Market

Learn more about the TAM - SAM - SOM Model starting on page 149 of 
The Handbook of Market Research for Life Science Companies [eBook] 
(Don't let the title fool you! This book is helpful for ALL industries, not just life sciences.)

 Estimating B2B Market Size

In a B2B (business-to-business) market, companies make up your pool of potential customers, or market size.

To estimate the size of a B2B market, you need to determine the number of companies in your target market. 

This can be approximated by creating a list of companies that meet specific criteria (e.g., industry, location, size, etc.)

 Estimating B2C Market Size

In a B2C (business-to-consumer) market, people make up your pool of potential customers, or market size.

To estimate the size of a B2C market, you need to determine the number of people in your target market. 

The following resources can help you approximate the number of people that meet various demographic or behavioral (psychographic) criteria:

For additional resources for estimating B2C market size, see the Consumers page.

It's helpful to understand:

1. Market size and share information is not always readily available, especially for small, niche industries. 

2. It may be necessary to estimate the market size by:

  • looking at a similar industry that can serve as a “proxy” or benchmark for your industry, or

  • using pieces of information from various sources to estimate the information you’re looking for.

3. Determining a company's market share for a product that accomplishes a specific task isn't clear-cut.

  • Companies rarely manufacture a single product (e.g., Apple manufactures phones, computers, watches, etc.).

  • A product rarely serves a single purpose (e.g., an Apple Watch monitors heart rate and counts counts steps).​

Bottom line:

The exact information you're looking for may not be available, and estimates may need to be made based on the information that is available.