market-sizing skill
Estimate market size using TAM, SAM, and SOM with top-down and bottom-up approaches. Use when sizing a market opportunity, estimating addressable market, preparing for investor pitches, or evaluating market entry.
Is the market-sizing skill safe?
Clean: nothing in its files matched our rules. We read 1 file in the folder on 2026-09-28.
No findings.
Install the market-sizing skill
A skill is a folder. Copy it into your agent's skills folder and the agent loads it when the task matches its description.
git clone --depth 1 https://github.com/phuryn/pm-skills.git /tmp/pm-skills mkdir -p ~/.claude/skills cp -r /tmp/pm-skills/pm-market-research/skills/market-sizing ~/.claude/skills/market-sizing
In the Claude apps, zip the folder and upload it from the Skills settings. The folder on GitHub
The instructions your agent would load
SKILL.md as published, without the frontmatter. Read it on GitHub
Estimate Market Size (TAM, SAM, SOM)
Purpose
Estimate the Total Addressable Market (TAM), Serviceable Addressable Market (SAM), and Serviceable Obtainable Market (SOM) for a product. Includes both top-down and bottom-up estimation approaches, growth projections, and key assumptions to validate.
Instructions
You are a strategic market analyst specializing in market sizing, opportunity assessment, and growth forecasting.
Input
Your task is to estimate the market size for $ARGUMENTS within the specified market constraints (geography, industry vertical, customer type, etc.).
If the user provides market research, industry reports, financial data, or competitor information, read and analyze them directly. Use web search to find current market data, industry reports, and growth projections.
Analysis Steps (Think Step by Step)
- Market Definition: Define the market boundaries — what problem space, which customer segments, what geography or constraints apply
- Top-Down Estimation: Start from total industry size and narrow to the relevant slice
- Bottom-Up Estimation: Build from unit economics (customers × price × frequency) to cross-validate
- SAM Scoping: Identify which portion of TAM is realistically serviceable given product capabilities, channels, and constraints
- SOM Estimation: Estimate achievable share in the next 1-3 years based on competitive position and go-to-market capacity
- Growth Projection: Forecast how TAM, SAM, and SOM may evolve over the next 2-3 years
- Assumption Mapping: Surface the key assumptions underlying each estimate
Output Structure
Market Definition
- Problem space and customer need
- Geographic and segment boundaries
- Key constraints or scoping decisions
TAM (Total Addressable Market)
- Top-down estimate with sources and reasoning
- Bottom-up estimate for cross-validation
- Reconciliation of the two approaches
- Current TAM value (annual revenue opportunity)
SAM (Serviceable Addressable Market)
- Which portion of TAM the product can realistically serve
- Constraints: geography, language, channels, product capabilities, pricing tier
- SAM as percentage of TAM with reasoning
SOM (Serviceable Obtainable Market)
- Realistic share achievable in 1-3 years
- Basis: competitive position, go-to-market capacity, current traction
- SOM as percentage of SAM with reasoning
Market Summary Table
Growth Drivers & Trends
- Key factors that could expand or contract the market
- Technology, regulatory, demographic, or behavioral shifts
- Emerging segments or adjacent markets
Key Assumptions & Risks
- Critical assumptions behind each estimate (numbered)
- Confidence level for each (high / medium / low)
- How to validate the most uncertain assumptions
- What would materially change the estimates
Best Practices
- Always provide both top-down and bottom-up estimates to triangulate
- Use web search for current industry data, analyst reports, and market benchmarks
- Cite sources for market data — avoid unsupported numbers
- Be explicit about assumptions; label estimates vs. data
- Distinguish between value-based (revenue) and volume-based (users/units) sizing
- Consider currency and purchasing power parity for international markets
- Flag where estimates have wide confidence intervals
- Recommend specific data sources or research to sharpen estimates
Further Reading
- Market Research: Advanced Techniques
- User Interviews: The Ultimate Guide to Research Interviews
- Crossing the Chasm: The Ultimate Guide For PMs
- Product Innovation Masterclass (video course)
More skills from phuryn/pm-skills
- Aab-test-analysisAnalyze A/B test results with statistical significance, sample size validation, confidence intervals, and ship/extend/stop recommendations. Use when evaluating experiment results, checking if a test reached significance, interpreting split test data, or deciding whether to ship a variant.
- Aanalyze-feature-requestsAnalyze and prioritize a list of feature requests by theme, strategic alignment, impact, effort, and risk. Use when reviewing customer feature requests, triaging a backlog, or making prioritization decisions.
- Aansoff-matrixGenerate an Ansoff Matrix analysis mapping growth strategies across market penetration, market development, product development, and diversification. Use when considering growth options, planning market expansion, or evaluating strategic growth paths.
- Abeachhead-segmentIdentify the first beachhead market segment for a product launch. Evaluates segments against burning pain, willingness to pay, winnable market share, and referral potential. Use when choosing a first market, targeting an initial customer segment, or planning market entry strategy.
- Abrainstorm-experiments-existingDesign experiments to test assumptions for an existing product — prototypes, A/B tests, spikes, and other low-effort validation methods. Use when validating assumptions, testing feature ideas cheaply, or planning product experiments.
- Abrainstorm-experiments-newDesign lean startup experiments (pretotypes) for a new product. Creates XYZ hypotheses and suggests low-effort validation methods like landing pages, explainer videos, and pre-orders. Use when validating a new product idea, creating pretotypes, or testing market demand.
- Abrainstorm-ideas-existingBrainstorm product ideas for an existing product using multi-perspective ideation from PM, Designer, and Engineer viewpoints. Use when generating new feature ideas, brainstorming solutions for an identified opportunity, or ideating with a product trio.
- Abrainstorm-ideas-newBrainstorm feature ideas for a new product in initial discovery from PM, Designer, and Engineer perspectives. Use when starting product discovery for a new product, exploring features for a startup idea, or doing initial ideation.
- Abrainstorm-okrsBrainstorm team-level OKRs aligned with company objectives — qualitative objectives with measurable key results. Use when setting quarterly OKRs, aligning team goals with company strategy, drafting objectives, or learning how to write effective OKRs.
- Abusiness-modelGenerate a Business Model Canvas with all 9 building blocks. Use when creating a business model, documenting how a business creates value, or analyzing an existing business model.
- Acode-reviewReview code for actionable defects. Correctness is the core; performance and security are optional sub-cases of the same engine. Anchors on agreements between participants across a boundary, forces a violating execution, and refutes every candidate before reporting. Use when asked to review changes, find bugs, audit a codebase, or check whether a fix is safe.
- Acohort-analysisPerform cohort analysis on user engagement data — retention curves, feature adoption trends, and segment-level insights. Use when analyzing user retention by cohort, studying feature adoption over time, investigating churn patterns, or identifying engagement trends.