Start Local, Not Global
Big national or world numbers look impressive, but they do not help a small business plan. A useful estimate starts from the customers you can actually reach — in your area, or through the channels you will really use.
You may see the terms TAM, SAM, and SOM. In plain words: the whole market, the part you can reach, and the part you can realistically win. For a small local business, the last two matter most.
Estimate Your Local Market
Local Market Size Calculator
Estimate how much your customers spend in a year. Everything is calculated on this page — nothing is sent or saved.
Market per year = customers × spend per purchase × purchases per year.
How to Find the Numbers
- Possible customers: count them — homes, offices, or businesses in your area — or use local government data. Your country's national statistics office often publishes population data by area.
- Spend per purchase: use your own prices, or what customers pay competitors today.
- How often they buy: ask 10–20 possible customers, or watch a similar business.
- Your share: be careful. A new business usually wins only a small part at first.
Example (Illustrative)
800 × 2.50 × 3 × 52 = about 312,000 a year spent on breakfast in the area.
A 15% share would be about 46,800 a year — close to the bakery's sales forecast of 45,000, so the forecast looks realistic.
Common Mistakes
- Using a whole country as your market.
- Assuming you will win a big share in your first year.
- Not saying where numbers come from. Always note your source.
Where It Fits in Your Business Plan
Your market estimate belongs in the Market Analysis section, with the source of your numbers. See also How to Do Market Research.
Frequently Asked Questions
How do I calculate market size for a small business?
Multiply the number of possible customers you can reach by how much they spend each time and how often they buy in a year.
What are TAM, SAM, and SOM?
The whole market (TAM), the part you can reach (SAM), and the part you can realistically win (SOM).
Where can I find data for my market size?
Count customers yourself, use local government or national statistics data, and ask possible customers how often they buy and how much they spend.
What market share should I expect?
It depends on your business and competitors. A new business usually wins only a small share at first, so be careful.
Build your plan with Founderplat
Founderplat walks you through all eight sections, one small step at a time, with tips and examples for every part.
Get the app on Google Play