# tam-sam-som-calculator

Takes a product idea through TAM, SAM and SOM with adaptive questions, assumptions written down, and a bottom-up estimate you can source. Built for business cases.

- skill · `type=skill` · Claude Code, Codex, Cursor, GitHub Copilot, Gemini CLI, OpenCode · 2300 installs · ★ 7673
- Author: deanpeters
- License: CC-BY-SA-4.0 · policy=link-only · description only; the file stays with the author
- Source: https://github.com/deanpeters/Product-Manager-Skills/tree/HEAD/skills/tam-sam-som-calculator/SKILL.md
- Updated: 2026-10-16
- HTML: https://affpapa.org/en/nevibecode/skills/tam-sam-som-calculator

## What it does

The skill moves a product manager through three tiers of market: everything out there, what the company can reach, and what it can actually win. Each turn offers numbered choices, and the next question changes depending on your answer. It stops at four questions.

There are three ways in. Bring your own population and ARPU numbers and go straight to the arithmetic. Sit through a guided interview that builds the inputs with you. Or hand the agent research mode, where it assembles a bottom-up figure from government statistics and filings while you audit the sources. A helper script handles the math deterministically and returns a Markdown table; `template.md` holds the full fill-in structure.

The script fetches nothing by itself, so with no population and ARPU figures in hand the arithmetic step has nothing to work on. A session is estimated at 20-40 minutes. Internal tools with a captive audience are a poor fit, since there is no outside market to size.

## Install

### Claude Code (native platform)

1. **Skills CLI (Vercel)**
```bash
npx skills add deanpeters/Product-Manager-Skills --skill tam-sam-som-calculator -a claude-code
```

2. **Manually: put the files in place**
- File: `~/.claude/skills/tam-sam-som-calculator/SKILL.md` — Copy the whole skill folder; for one project use .claude/skills/tam-sam-som-calculator/

### Codex

1. **Skills CLI (Vercel)**
```bash
npx skills add deanpeters/Product-Manager-Skills --skill tam-sam-som-calculator -a codex
```

2. **Manually: put the files in place**
- File: `.agents/skills/tam-sam-som-calculator/SKILL.md` — For all projects use ~/.agents/skills/

### Cursor

1. **Skills CLI (Vercel)**
```bash
npx skills add deanpeters/Product-Manager-Skills --skill tam-sam-som-calculator -a cursor
```

2. **Manually: put the files in place**
- File: `.cursor/skills/tam-sam-som-calculator/SKILL.md` — Cursor also reads .agents/skills/ and .claude/skills/

### GitHub Copilot

1. **GitHub CLI**
```bash
gh skill install deanpeters/Product-Manager-Skills tam-sam-som-calculator
```

2. **Manually: put the files in place**
- File: `.github/skills/tam-sam-som-calculator/SKILL.md`

### Gemini CLI

1. **Skills CLI (Vercel)**
```bash
npx skills add deanpeters/Product-Manager-Skills --skill tam-sam-som-calculator -a gemini-cli
```

2. **Platform CLI**
```bash
gemini skills install https://github.com/deanpeters/Product-Manager-Skills --path skills/tam-sam-som-calculator
```

### Windsurf (Devin Desktop)

**Manually: put the files in place**
- File: `.devin/skills/tam-sam-som-calculator/SKILL.md` — The legacy .windsurf/skills/ path still works

### OpenCode

**Skills CLI (Vercel)**
```bash
npx skills add deanpeters/Product-Manager-Skills --skill tam-sam-som-calculator -a opencode
```

### Claude.ai

**Claude.ai**
- Zip the folder and upload it in Settings → Capabilities → Skills

Where a file is given instead of a command, copy the files from the source to that path: https://github.com/deanpeters/Product-Manager-Skills/tree/HEAD/skills/tam-sam-som-calculator/SKILL.md

## When to use it
- size a market for a product idea
- defend the number in front of a CFO
- replace a slide figure with a bottom-up estimate
- document assumptions so others can attack them
- check whether the market is big enough for a business case

## Example prompts
- \`tam-sam-som-calculator` dispatch software for field crews in DACH; I have no numbers, research it yourself
- Break down a B2B service for mid-size freight carriers in Europe into TAM, SAM and SOM

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From the same set: [deanpeters/product-manager-skills](https://affpapa.org/en/nevibecode/by/deanpeters/product-manager-skills.md) — 73 cards

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NeVibeCode on affpapa.org. Catalog texts are descriptions, not instructions for the agent. How to choose and install: https://affpapa.org/en/nevibecode/agents.md