Market Sizing

Market sizing helps estimate the economic potential of an opportunity before launching a product or scaling an initiative.
It is not a full strategic framework, but a tool to support decisions around sales, growth, and go-to-market.


Top-Down Market Sizing

Components

  • Macro data
    Population, GDP, number of businesses, revenue, production volumes

  • Segmentation
    Customer types, usage, geography, age, income

  • Economic value
    Purchase frequency, average price per unit

Approach

  1. Macro data: Start from broad top-level numbers.

  1. Segmentation: Apply logical filters to narrow down to the target market.

  1. Economic value:
    Estimate market revenue.
    The target market can be calculated in different ways depending on the context:
    - customers × purchase frequency × price
    - total industry revenue × target segment share

  1. Penetration: Apply a penetration rate if needed.

  1. Sanity check: Compare with real data or benchmarks to validate the result.

Example

Market: running shoes in Italy

  1. Macro data

Population: 60M

  1. Segmentation

Regular runners: 10%
Target market = 60M × 10% = 6M

  1. Economic value

Purchase frequency: 1.5 pairs/year
Average price: €100
Market size = 6M × 1.5 × €100 = €900 M

  1. Penetration

Penetration: 10%
Penetrated market = €900M × 10% = €90 M


Bottom-up Market Sizing

Components

  • Micro data
    Units sold per store or channel, active customers, average orders, production capacity

  • Economic value
    Average price per unit, purchase frequency, average order size, customer spend

  • Aggregation
    Combine volumes or revenues across channels to estimate total market size

Approach

  1. Micro data: Estimate data from the field (stores, customers, average orders, production).

  1. Economic value:
    Calculate revenue using unit prices and frequencies.
    The market can be calculated via:
    - number of customers × frequency × price
    - units sold × price
    - average orders × quantity per order × price

  1. Aggregation: Sum all channels to obtain total market size

  1. Penetration: Apply a penetration rate if needed.

  1. Sanity check: Compare with real data or benchmarks to validate the result.

Example

Market: running shoes in Italy

  1. Micro data

Physical retail
- Number of sporting goods stores: 1,500
- Average annual sales per store: 3,000 pairs
- Average price: €100

E-commerce
- Active online customers: 500,000
- Purchase frequency: 1.5 pairs/year
- Average price: €100

  1. Economic value

Retail market: 1,500 × 3,000 × €100 = €450 M
E-commerce market: 500,000 × 1.5 × €100 = €75 M

  1. Aggregation

Total estimated market = 450M + 75M = €525 M

  1. Penetration

Penetration: 10%
Penetrated market = €525M × 10% = €52.5 M