Market Size & Opportunity Estimator
Estimate your total addressable market (TAM), serviceable market (SAM), and obtainable market (SOM) using a bottoms-up approach. Produces investor-ready market sizing with documented assumptions and multiple estimation methods for cross-validation.
Start with the narrowest, most defensible number you can — your SOM. Investors and partners respect bottoms-up math from real data points more than inflated top-down TAM claims.
How to use this prompt
- Pick your AI model. Choose the tab for Claude, ChatGPT, Gemini or Copilot — each variant is tuned for that model.
- Copy the full prompt. Click Copy Full Prompt to copy the text to your clipboard.
- Paste into your AI tool. Open your chosen model and paste the prompt into a new chat.
- Replace the
[placeholders]. Swap any bracketed fields for your company name, audience, product or tone. - Run and refine. Review the output. If anything is off, ask the AI to tighten tone, length or format.
Prompt Variants by Model
You are a market research analyst building a market sizing model.
<business>
Product/service: [WHAT YOU SELL]
Price point: [AMOUNT per unit/month/year]
Target customer: [WHO — be specific: role,...You are a market research analyst building a market sizing model.
<business>
Product/service: [WHAT YOU SELL]
Price point: [AMOUNT per unit/month/year]
Target customer: [WHO — be specific: role, company size, industry, geography]
Current customers: [NUMBER, if any]
Current revenue: [AMOUNT, if any]
Geographic scope: [local / national / global]
</business>
Build a market sizing analysis:
1. **Top-down estimate** — start with the broadest industry figure and narrow to your segment. Document every filter and its source/assumption.
2. **Bottoms-up estimate** — calculate from: number of potential customers × your price × expected penetration rate. Show the math.
3. **TAM / SAM / SOM** — clearly define and calculate each:
- TAM: total demand if you had no constraints
- SAM: the segment you can realistically reach with your current model
- SOM: what you can capture in the next 12-24 months with current resources
4. **Assumption table** — every assumption listed with confidence level (high/medium/low) and data source.
5. **Sensitivity analysis** — what happens to SOM if your core assumptions move ±30%?
6. **Comparable benchmarks** — similar companies or market reports that validate the range.
7. **One-paragraph summary** — investor-ready market opportunity statement.Act as a market research analyst. Build a market sizing model for my business.
Product: [WHAT]
Price:...Act as a market research analyst. Build a market sizing model for my business.
Product: [WHAT]
Price: [AMOUNT]
Target: [WHO — role, company size, industry, geography]
Current customers: [NUMBER]
Current revenue: [AMOUNT]
Geography: [local / national / global]
Deliver:
1. Top-down estimate with filters documented
2. Bottoms-up estimate with math shown
3. TAM / SAM / SOM with clear definitions
4. Assumption table with confidence levels
5. Sensitivity analysis (±30% on core assumptions)
6. Comparable benchmarks
7. Investor-ready one-paragraph summaryBuild a market sizing model for my business.
**Product:** [WHAT]
**Price:** [AMOUNT]
**Target:**...Build a market sizing model for my business.
**Product:** [WHAT]
**Price:** [AMOUNT]
**Target:** [WHO]
**Current customers:** [NUMBER]
**Revenue:** [AMOUNT]
**Geography:** [scope]
Research current market data, industry reports, and comparable companies, then:
1. Top-down estimate with sourced filters
2. Bottoms-up estimate with math
3. TAM / SAM / SOM
4. Assumption table with confidence levels and sources
5. Sensitivity analysis (±30%)
6. Comparable benchmarks with citations
7. Investor-ready summary paragraphBuild a market sizing analysis.
Product: [WHAT]
Price:...Build a market sizing analysis.
Product: [WHAT]
Price: [AMOUNT]
Target: [WHO]
Customers: [NUMBER]
Revenue: [AMOUNT]
Geography: [scope]
Deliver:
1. Top-down estimate
2. Bottoms-up estimate with math
3. TAM / SAM / SOM
4. Assumptions table
5. Sensitivity analysis
6. Benchmarks
7. Summary paragraphFrequently Asked Questions
What does the Market Size & Opportunity Estimator prompt do?
Estimate your total addressable market (TAM), serviceable market (SAM), and obtainable market (SOM) using a bottoms-up approach. Produces investor-ready market sizing with documented assumptions and multiple estimation methods for cross-validation.
Which AI models is this prompt tested on?
This prompt is field-tested on Claude, ChatGPT, Gemini and Copilot. Each model has its own optimized variant above.
Do I need a paid AI account to use this prompt?
No. This prompt is written to run on the free tier of Claude, ChatGPT, Gemini and Copilot. Paid tiers simply give you longer context windows and faster responses.
Can I customize this prompt for my business?
Yes. Any text inside square brackets is a placeholder you replace with your own business details, such as company name, audience, product or tone. You can also ask the AI to adjust format, length or style after the first output.
When was this prompt last verified?
Each model variant above shows its own freshness stamp. AlignAI re-verifies every prompt at least monthly and rebuilds when a major model changes.
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