# Market Sizing

> Size a startup's market credibly, top-down and bottom-up, and pressure-test the story.

- Skill: `tinyhumansai/market-sizing` (Agent Skill)
- Install (CLI): `npx skillmds@latest add tinyhumansai/market-sizing`
- Raw SKILL.md: https://api.skillmd.com/api/skills/tinyhumansai/market-sizing/raw
- Safety review: pending (external: skill-scanner PASS, skillspector PASS)
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: tinyhumansai (https://skillmd.com/u/tinyhumansai)
- Updated: 2026-09-22
- Page: https://skillmd.com/skills/tinyhumansai/market-sizing

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# Market Sizing

Judge whether a startup's market is big enough and real — sized two ways and
tested against the pitch.

## When to use

- A deal's market claim needs standing up in diligence.
- A founder's TAM looks too clean to trust.

## Steps

1. **Define** the market the company actually serves, not the adjacent dream.
2. **Size** it top-down from credible aggregates.
3. **Size** it bottom-up from customers × price × frequency.
4. **Reconcile** the two and explain the gap.
5. **Test** the growth story against real drivers.

## Output

A sized market with both methods reconciled and the growth story assessed,
following the [[Investment thesis]]. Feeds the diligence and the memo.