Agent skill · product strategy · yonatangross
market-sizing
TAM, SAM and SOM with top-down and bottom-up estimates and cross-checked assumptions. Use when sizing a market or preparing pitch market slides.
Why this skill is useful
Provides detailed methodologies and formulas for market sizing that the AI wouldn't reliably generate on its own.
What it needs
About 3k tokens when loaded. Last updated 2026-08-06. 215 stars on the source repository.
What this skill does
Market Sizing TAM/SAM/SOM framework for estimating addressable market and validating opportunity size. Definitions Metric Definition Question It Answers -------- ------------ --------------------- TAM Total Addressable Market — everyone who could possibly buy "What's the theoretical ceiling?" SAM Serviceable Addressable Market — segment you can actually reach "What can we realistically target?" SOM Serviceable Obtainable Market — realistic share in 3 years "What will we actually capture?" When to Use Top-Down vs. Bottom-Up Method Use When Risk -------- ---------- ------ Top-Down Industry reports exist; investor pitch; quick estimate Overestimates SOM Bottom-Up Sales capacity known; pricing validated; more credible More work; requires assumptions Both (recommended) High-stakes decisions; fundraising; board decks Cross-validate to build confidence Always cross-validate both methods and reconcile within 20%. If they diverge by more than that, revisit your assumptions. Quick Formulas Example: AI Code Review Tool SOM Constraint Model Do not report an unconstrained SOM. Always apply real-world limits: Confidence Levels Confidence Evidence Required ------------ ------------------ HIGH Multiple corroborating sources, data < 2 years old MEDIUM Single authoritative source, 1-2 years old LOW Extrapolated, heavy assumptions, data > 2 years old Always label each number with its confidence level in deliverables. …
How to use it
Reference it in AdaL, Claude Code, Cursor or any coding agent — nothing to install:
@skills yonatangross/market-sizing--90e95a