market-sizing

Calculate TAM, SAM, and SOM with top-down or bottom-up methodologies.

26|1|Updated Feb 21, 2026

Search Tags:#business strategy #market research #market sizing #startup fundraising #tam sam som #investor analysis

Ready to run

npx skills add https://github.com/lool-ventures/founder-skills --skill market-sizing-lool-ventures

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: market-sizing
Source: https://github.com/lool-ventures/founder-skills/tree/main/founder-skills/skills/market-sizing
Command: npx skills add https://github.com/lool-ventures/founder-skills --skill market-sizing-lool-ventures

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes scripts (resource) and references (resource) components.

What problem does it solve?

This Skill helps founders build credible, defensible TAM/SAM/SOM analysis that earns investor trust, moving beyond guesswork to data-backed estimates.

Core Features & Use Cases

Automated Market Sizing: Calculates TAM, SAM, and SOM using top-down, bottom-up, or both methodologies.
External Validation: Researches and validates market claims against external data sources.
Sensitivity Analysis: Stress-tests assumptions to understand best-case and worst-case scenarios.
Use Case: A founder can provide a pitch deck or business description, and the Skill will produce a structured report with validated market size figures, sensitivity ranges, and a self-check against common pitfalls.

Quick Start

Use the market-sizing skill to analyze the market for a new fintech app targeting SMBs in Europe.

Frequently Asked Questions about market-sizing

High-intent search queries and answers about installing and using this skill.

FAQPage Schema

How do I calculate TAM, SAM, and SOM for startup fundraising?▼

You can calculate TAM, SAM, and SOM using top-down, bottom-up, or dual methodologies. This skill computes market sizes, validates claims against external data, and runs sensitivity analysis for credible startup fundraising estimates.

What is the difference between top-down and bottom-up market sizing?▼

Top-down market sizing starts from total industry revenue and narrows down, while bottom-up builds estimates from individual unit pricing and customer counts. This skill supports both approaches to calculate TAM, SAM, and SOM.

How do I validate market size estimates against external data?▼

Validating market size estimates against external data involves researching external sources to confirm claims. This skill automatically researches and validates your TAM, SAM, and SOM figures against external data sources to ensure credibility.

Do I need Python to run market sizing analysis?▼

Yes, you need Python 3.10+ and uv installed to run the market sizing scripts. These tools execute the calculations, validate external data, perform sensitivity analysis, and generate the final TAM SAM SOM report.

Can I stress-test startup market assumptions for best and worst-case scenarios?▼

You can stress-test startup market assumptions using sensitivity analysis. This skill evaluates your inputs to model best-case and worst-case scenarios, helping you understand the potential variance in your TAM, SAM, and SOM projections.

What are common pitfalls when estimating Total Addressable Market?▼

Common pitfalls when estimating Total Addressable Market include unsupported assumptions and methodology errors. This skill checks your analysis against a 22-item checklist to identify and prevent common market sizing mistakes.