What is the difference between TAM, SAM, and SOM?

TAM (Total Addressable Market) is the total global opportunity, SAM (Serviceable Available Market) is the portion you can realistically target with your current product and geography, and SOM (Serviceable Obtainable Market) is the share you expect to capture in 3-5 years.

Does this skill work for SaaS and Marketplace business models?

Yes, it includes specific calculation templates for SaaS (using ACV and expansion rates) and marketplaces (using GMV and take rates).

How can I ensure my market sizing is accurate?

The skill suggests 'triangulating' your results by comparing top-down and bottom-up figures; if they are within 30% of each other, your model is generally considered robust.

Why is bottom-up analysis preferred over top-down?

Investors prefer bottom-up analysis because it is built from granular data like customer segments and specific pricing models, making it more defensible and realistic than broad industry reports.

Market Sizing Analysis

Name: Market Sizing Analysis
Author: ngxtm

byngxtm

•

Productivity & Workflow

Calculates Total Addressable Market (TAM), Serviceable Available Market (SAM), and Serviceable Obtainable Market (SOM) using data-backed methodologies.

This skill provides a comprehensive framework for evaluating business opportunities through structured market sizing analysis. It guides users through top-down, bottom-up, and value theory methodologies to estimate TAM, SAM, and SOM with precision. Designed for founders, product managers, and developers, it assists in defining market scope, identifying credible data sources, and validating assumptions to create defensible projections. Whether preparing for a venture capital pitch or conducting internal strategy sessions, this skill offers the specialized formulas and industry-specific logic—including SaaS and marketplace models—needed to quantify market potential accurately.

Key Features

01Triangulation techniques to cross-check results and identify common sizing errors

02Standardized calculation formulas for TAM, SAM, and SOM with realistic capture rates

03Industry-specific metrics for SaaS, Marketplaces, B2B services, and Consumer markets

04Three-methodology framework including Top-Down, Bottom-Up, and Value Theory analysis

054 GitHub stars

06Step-by-step workflow for data gathering, market definition, and validation

Use Cases

01Quantifying market opportunity for a new product launch or startup venture

02Generating data-backed market analysis for investor pitch decks and fundraising

03Prioritizing target customer segments based on potential revenue impact

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add ngxtm/devkit market-sizing-analysis

For use in Claude.ai and ChatGPT

Key Features

01Triangulation techniques to cross-check results and identify common sizing errors

02Standardized calculation formulas for TAM, SAM, and SOM with realistic capture rates

03Industry-specific metrics for SaaS, Marketplaces, B2B services, and Consumer markets

04Three-methodology framework including Top-Down, Bottom-Up, and Value Theory analysis

054 GitHub stars

06Step-by-step workflow for data gathering, market definition, and validation

Use Cases

01Quantifying market opportunity for a new product launch or startup venture

02Generating data-backed market analysis for investor pitch decks and fundraising

03Prioritizing target customer segments based on potential revenue impact