--- name: market-sizing-analysis description: This skill should be used when the user asks to \\\"calculate TAM\\\", "determine SAM", "estimate SOM", "size the market", "calculate market opportunity", "what's the total addressable market", or... risk: unknown source: community date_added: '2026-02-27' --- # Market Sizing Analysis Comprehensive market sizing methodologies for calculating Total Addressable Market (TAM), Serviceable Available Market (SAM), and Serviceable Obtainable Market (SOM) for startup opportunities. ## Use this skill when - Working on market sizing analysis tasks or workflows - Needing guidance, best practices, or checklists for market sizing analysis ## Do not use this skill when - The task is unrelated to market sizing analysis - You need a different domain or tool outside this scope ## Instructions - Clarify goals, constraints, and required inputs. - Apply relevant best practices and validate outcomes. - Provide actionable steps and verification. - If detailed examples are required, open `resources/implementation-playbook.md`. ## Overview Market sizing provides the foundation for startup strategy, fundraising, and business planning. Calculate market opportunity using three complementary methodologies: top-down (industry reports), bottom-up (customer segment calculations), and value theory (willingness to pay). ## Core Concepts ### The Three-Tier Market Framework **TAM (Total Addressable Market)** - Total revenue opportunity if achieving 100% market share - Defines the universe of potential customers - Used for long-term vision and market validation - Example: All email marketing software revenue globally **SAM (Serviceable Available Market)** - Portion of TAM targetable with current product/service - Accounts for geographic, segment, or capability constraints - Represents realistic addressable opportunity - Example: AI-powered email marketing for e-commerce in North America **SOM (Serviceable Obtainable Market)** - Realistic market share achievable in 3-5 years - Accounts for competition, resources, and market dynamics - Used for financial projections and fundraising - Example: 2-5% of SAM based on competitive landscape ### When to Use Each Methodology **Top-Down Analysis** - Use when established market research exists - Best for mature, well-defined markets - Validates market existence and growth - Starts with industry reports and narrows down **Bottom-Up Analysis** - Use when targeting specific customer segments - Best for new or niche markets - Most credible for investors - Builds from customer data and pricing **Value Theory** - Use when creating new market categories - Best for disruptive innovations - Estimates based on value creation - Calculates willingness to pay for problem solution ## Three-Methodology Framework ### Methodology 1: Top-Down Analysis Start with total market size and narrow to addressable segments. **Process:** 1. Identify total market category from research reports 2. Apply geographic filters (target regions) 3. Apply segment filters (target industries/customers) 4. Calculate competitive positioning adjustments **Formula:** ``` TAM = Total Market Category Size SAM = TAM × Geographic % × Segment % SOM = SAM × Realistic Capture Rate (2-5%) ``` **When to use:** Established markets with available research (e.g., SaaS, fintech, e-commerce) **Strengths:** Quick, uses credible data, validates market existence **Limitations:** May overestimate for new categories, less granular ### Methodology 2: Bottom-Up Analysis Build market size from customer segment calculations. **Process:** 1. Define target customer segments 2. Estimate number of potential customers per segment 3. Determine average revenue per customer 4. Calculate realistic penetration rates **Formula:** ``` TAM = Σ (Segment Size × Annual Revenue per Customer) SAM = TAM × (Segments You Can Serve / Total Segments) SOM = SAM × Realistic Penetration Rate (Year 3-5) ``` **When to use:** B2B, niche markets, specific customer segments **Strengths:** Most credible for investors, granular, defensible **Limitations:** Requires detailed customer research, time-intensive ### Methodology 3: Value Theory Calculate based on value created and willingness to pay. **Process:** 1. Identify problem being solved 2. Quantify current cost of problem (time, money, inefficiency) 3. Calculate value of solution (savings, gains, efficiency) 4. Estimate willingness to pay (typically 10-30% of value) 5. Multiply by addressable customer base **Formula:** ``` Value per Customer = Problem Cost × % Solved by Solution Price per Customer = Value × Willingness to Pay % (10-30%) TAM = Total Potential Customers × Price per Customer SAM = TAM × % Meeting Buy Criteria SOM = SAM × Realistic Adoption Rate ``` **When to use:** New categories, disruptive innovations, unclear existing markets **Strengths:** Shows value creation, works for new markets **Limitations:** Requires assumptions, harder to validate ## Step-by-Step Process ### Step 1: Define the Market Clearly specify what market is being measured. **Questions to answer:** - What problem is being solved? - Who are the target customers? - What's the product/service category? - What's the geographic scope? - What's the time horizon? **Example:** - Problem: E-commerce companies struggle with email marketing automation - Customers: E-commerce stores with >$1M annual revenue - Category: AI-powered email marketing software - Geography: North America initially, global expansion - Horizon: 3-5 year opportunity ### Step 2: Gather Data Sources Identify credible data for calculations. **Top-Down Sources:** - Industry research reports (Gartner, Forrester, IDC) - Government statistics (Census, BLS, trade associations) - Public company filings and earnings - Market research firms (Statista, CB Insights, PitchBook) **Bottom-Up Sources:** - Customer interviews and surveys - Sales data and CRM records - Industry databases (LinkedIn, ZoomInfo, Crunchbase) - Competitive intelligence - Academic research **Value Theory Sources:** - Customer problem quantification - Time/cost studies - ROI case studies - Pricing research and willingness-to-pay surveys ### Step 3: Calculate TAM Apply chosen methodology to determine total market. **For Top-Down:** 1. Find total category size from research 2. Document data source and year 3. Apply growth rate if needed 4. Validate with multiple sources **For Bottom-Up:** 1. Count total potential customers 2. Calculate average annual revenue per customer 3. Multiply to get TAM 4. Break down by segment **For Value Theory:** 1. Quantify total addressable customer base 2. Calculate value per customer 3. Estimate pricing based on value 4. Multiply for TAM ### Step 4: Calculate SAM Narrow TAM to serviceable addressable market. **Apply Filters:** - Geographic constraints (regions you can serve) - Product limitations (features you currently have) - Customer requirements (size, industry, use case) - Distribution channel access - Regulatory or compliance restrictions **Formula:** ``` SAM = TAM × (% matching all filters) ``` **Example:** - TAM: $10B global email marketing - Geographic filter: 40% (North America) - Product filter: 30% (e-commerce focus) - Feature filter: 60% (need AI capabilities) - SAM = $10B × 0.40 × 0.30 × 0.60 = $720M ### Step 5: Calculate SOM Determine realistic obtainable market share. **Consider:** - Current market share of competitors - Typical market share for new entrants (2-5%) - Resources available (funding, team, time) - Go-to-market effectiveness - Competitive advantages - Time to achieve (3-5 years typically) **Conservative Approach:** ``` SOM (Year 3) = SAM × 2% SOM (Year 5) = SAM × 5% ``` **Example:** - SAM: $720M - Year 3 SOM: $720M × 2% = $14.4M - Year 5 SOM: $720M × 5% = $36M ### Step 6: Validate and Triangulate Cross-check using multiple methods. **Validation Techniques:** 1. Compare top-down and bottom-up results (should be within 30%) 2. Check against public company revenues in space 3. Validate customer count assumptions 4. Sense-check pricing assumptions 5. Review with industry experts 6. Compare to similar market categories **Red Flags:** - TAM that's too small (< $1B for VC-backed startups) - TAM that's too large (unsupported by data) - SOM that's too aggressive (> 10% in 5 years for new entrant) - Inconsistency between methodologies (> 50% difference) ## Industry-Specific Considerations ### SaaS Markets **Key Metrics:** - Number of potential businesses in target segment - Average contract value (ACV) - Typical market penetration rates - Expansion revenue potential **TAM Calculation:** ``` TAM = Total Target Companies × Average ACV × (1 + Expansion Rate) ``` ### Marketplace Markets **Key Metrics:** - Gross Merchandise Value (GMV) of category - Take rate (% of GMV you capture) - Total transactions or users **TAM Calculation:** ``` TAM = Total Category GMV × Expected Take Rate ``` ### Consumer Markets **Key Metrics:** - Total addressable users/households - Average revenue per user (ARPU) - Engagement frequency **TAM Calculation:** ``` TAM = Total Users × ARPU × Purchase Frequency per Year ``` ### B2B Services **Key Metrics:** - Number of target companies by size/industry - Average project value or retainer - Typical buying frequency **TAM Calculation:** ``` TAM = Total Target Companies × Average Deal Size × Deals per Year ``` ## Presenting Market Sizing ### For Investors **Structure:** 1. Market definition and problem scope 2. TAM/SAM/SOM with methodology 3. Data sources and assumptions 4. Growth projections and drivers 5. Competitive landscape context **Key Points:** - Lead with bottom-up calculation (most credible) - Show triangulation with top-down - Explain conservative assumptions - Link to revenue projections - Highlight market growth rate ### For Strategy **Structure:** 1. Addressable customer segments 2. Prioritization by opportunity size 3. Entry strategy by segment 4. Expected penetration timeline 5. Resource requirements **Key Points:** - Focus on SAM and SOM - Show segment-level detail - Connect to go-to-market plan - Identify expansion opportunities - Discuss competitive positioning ## Common Mistakes to Avoid **Mistake 1: Confusing TAM with SAM** - Don't claim entire market as addressable - Apply realistic product/geographic constraints - Be honest about serviceable market **Mistake 2: Overly Aggressive SOM** - New entrants rarely capture > 5% in 5 years - Account for competition and resources - Show realistic ramp timeline **Mistake 3: Using Only Top-Down** - Investors prefer bottom-up validation - Top-down alone lacks credibility - Always triangulate with multiple methods **Mistake 4: Cherry-Picking Data** - Use consistent, recent data sources - Don't mix methodologies inappropriately - Document all assumptions clearly **Mistake 5: Ignoring Market Dynamics** - Account for market growth/decline - Consider competitive intensity - Factor in switching costs and barriers ## Additional Resources ### Reference Files For detailed methodologies and frameworks: - **`references/methodology-deep-dive.md`** - Comprehensive guide to each methodology with step-by-step worksheets - **`references/data-sources.md`** - Curated list of market research sources, databases, and tools - **`references/industry-templates.md`** - Specific templates for SaaS, marketplace, consumer, B2B, and fintech markets ### Example Files Working examples with complete calculations: - **`examples/saas-market-sizing.md`** - Complete TAM/SAM/SOM for a B2B SaaS product - **`examples/marketplace-sizing.md`** - Marketplace platform market opportunity calculation - **`examples/value-theory-example.md`** - Value-based market sizing for disruptive innovation Use these examples as templates for your own market sizing analysis. Each includes real numbers, data sources, and assumptions documented clearly. ## Quick Start To perform market sizing analysis: 1. **Define the market** - Problem, customers, category, geography 2. **Choose methodology** - Bottom-up (preferred) or top-down + triangulation 3. **Gather data** - Industry reports, customer data, competitive intelligence 4. **Calculate TAM** - Apply methodology formula 5. **Narrow to SAM** - Apply product, geographic, segment filters 6. **Estimate SOM** - 2-5% realistic capture rate 7. **Validate** - Cross-check with alternative methods 8. **Document** - Show methodology, sources, assumptions 9. **Present** - Structure for audience (investors, strategy, operations) For detailed step-by-step guidance on each methodology, reference the files in `references/` directory. For complete worked examples, see `examples/` directory.