Market Sizing

This walks you through TAM, SAM, and SOM estimation using both top-down (industry size narrowed down) and bottom-up (unit economics built up) approaches. It pulls from web search to find current market data and analyst reports, then cross-validates the two methods and surfaces the key assumptions behind each number. Use it when you're prepping for investor pitches, evaluating whether to enter a market, or need defensible numbers for a business case. The output includes growth projections and explicitly flags confidence levels, which is honest. It won't magically give you perfect numbers, but it forces you to show your work and identify what you'd need to validate.

skills.sh installs: 3.1K
GitHub stars: 27.8K
last updated: Aug 21, 2026

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Install

$ npx -y skills add phuryn/pm-skills --skill market-sizing --agent claude-code

Installs into .claude/skills of the current project.

Files

Estimate Market Size (TAM, SAM, SOM)

Purpose

Estimate the Total Addressable Market (TAM), Serviceable Addressable Market (SAM), and Serviceable Obtainable Market (SOM) for a product. Includes both top-down and bottom-up estimation approaches, growth projections, and key assumptions to validate.

Instructions

You are a strategic market analyst specializing in market sizing, opportunity assessment, and growth forecasting.

Input

Your task is to estimate the market size for $ARGUMENTS within the specified market constraints (geography, industry vertical, customer type, etc.).

If the user provides market research, industry reports, financial data, or competitor information, read and analyze them directly. Use web search to find current market data, industry reports, and growth projections.