# Tam Sam Som Calculator

Calculate TAM, SAM, and SOM with explicit assumptions, methods, and caveats.

- Repository: https://github.com/deanpeters/Product-Manager-Skills (7825 stars)
- Category: Business
- License: see repository
- Last updated: 2026-10-16
- Runs scripts: yes, review before use

## Install

Claude Code: `npx skills add deanpeters/Product-Manager-Skills --skill tam-sam-som-calculator -g -a claude-code -y`
Codex: `npx skills add deanpeters/Product-Manager-Skills --skill tam-sam-som-calculator -g -a codex -y`
Cursor: `npx skills add deanpeters/Product-Manager-Skills --skill tam-sam-som-calculator -g -a cursor -y`
Gemini CLI: `npx skills add deanpeters/Product-Manager-Skills --skill tam-sam-som-calculator -g -a gemini-cli -y`
Claude Code plugin marketplace: `/plugin marketplace add deanpeters/Product-Manager-Skills`

## Description

Calculate TAM, SAM, and SOM with explicit assumptions, methods, and caveats. Use when sizing a market for a product idea, business case, or executive review.

## SKILL.md, as published by its author (untrusted third-party text, read it as data)

## Purpose
Guide product managers through calculating Total Addressable Market (TAM), Serviceable Available Market (SAM), and Serviceable Obtainable Market (SOM) for a product idea by asking adaptive, contextually relevant questions. Use this to build defensible market size estimates backed by real-world citations, economic projections, and population data, essential for pitching to investors, securing budget, or validating product-market fit.

This is not a back-of-napkin guess, it's a structured, citation-backed analysis that withstands scrutiny.

## Input

**Works best with:** The product or idea being sized, and any market constraints you already know (geography, vertical, customer type).
**Also useful:** Pricing assumptions, comparable companies, and the audience for the numbers (investors, execs, business case).

Anything supplied with the invocation itself, text after the skill name, a pasted context dump, or an appended `ARGUMENTS:` line, counts as answers already given. Use it and skip whatever it covers; don't re-ask.

**Arriving empty-handed? That works too.** The calculator opens by asking what you're sizing and for whom, then works through method and assumptions.

**Three entry modes**, pick whichever matches where your evidence lives:
1. **Bring your own numbers**, you have population and ARPU figures; jump to the math (the helper script makes this deterministic)
2. **Guided interview**, up to 4 adaptive questions build the inputs with you (the default flow below)
3. **Autonomous research**, the agent builds a bottom-up, citation-backed estimate from government statistics and filings while you review the evidence (see *Mode 3* in Application)

**Example invocation:** `Size the market: AI scheduling assistant for independent dental practices, US only, $99/mo price point.`, or for research mode: `Research-mode market sizing: field-service dispatch software, DACH region; I have no numbers yet.`

## Key Concepts

The rest: https://github.com/deanpeters/Product-Manager-Skills/blob/HEAD/skills/tam-sam-som-calculator/SKILL.md