Bottom-up Market Sizing

A market analysis approach that builds market size estimates from individual customer data and unit economics.

Definition

Bottom-up market sizing starts with specific, granular data about individual customers, pricing, and usage patterns to build up to a total market estimate. This approach provides more accurate and defensible market size calculations by using real customer behavior and economics.

Methodology

1. Define Target Customer

Identify specific customer segments and their characteristics

2. Count Potential Customers

Research and quantify the number of target customers

3. Estimate Customer Value

Calculate average revenue per customer or unit economics

4. Apply Penetration Rate

Estimate realistic adoption or conversion rates

5. Calculate Total Market

Multiply customers × value × penetration rate

Formula

Basic Bottom-Up Formula:

Market Size = Number of Target Customers × Average Revenue Per Customer × Market Penetration %

Example Components:

• Target customers: Companies with 50-500 employees
• ARPC: $2,000 per year per customer
• Penetration: 5% realistic adoption rate

Real-World Example

HR Software for Mid-Market Companies:

  • • Target: US companies with 100-1,000 employees
  • • Count: 50,000 companies (from census data)
  • • ARPC: $5,000 annual software spend per company
  • • Penetration: 20% likely to adopt new HR software
  • • Market Size = 50,000 × $5,000 × 20% = $50 million

This gives a realistic, data-driven market size estimate.

Advantages vs Top-Down

Bottom-Up Benefits

  • • More accurate estimates
  • • Based on real customer data
  • • Easier to validate assumptions
  • • Useful for operations planning
  • • Credible with investors

Potential Limitations

  • • Requires detailed research
  • • May miss market expansion
  • • Time-intensive to build
  • • Assumptions may be conservative

Related Terms