Back to skills
SkillHub ClubShip Full StackFull Stack

tam-sam-som-calculator

Calculate TAM, SAM, and SOM with explicit assumptions, methods, and caveats. Use when sizing a market for a product idea, business case, or executive review.

Packaged view

This page reorganizes the original catalog entry around fit, installability, and workflow context first. The original raw source lives below.

Stars
2,100
Hot score
99
Updated
March 20, 2026
Overall rating
C4.0
Composite score
4.0
Best-practice grade
B77.6

Install command

npx @skill-hub/cli install deanpeters-product-manager-skills-tam-sam-som-calculator

Repository

deanpeters/Product-Manager-Skills

Skill path: skills/tam-sam-som-calculator

Calculate TAM, SAM, and SOM with explicit assumptions, methods, and caveats. Use when sizing a market for a product idea, business case, or executive review.

Open repository

Best for

Primary workflow: Ship Full Stack.

Technical facets: Full Stack.

Target audience: everyone.

License: Unknown.

Original source

Catalog source: SkillHub Club.

Repository owner: deanpeters.

This is still a mirrored public skill entry. Review the repository before installing into production workflows.

What it helps with

  • Install tam-sam-som-calculator into Claude Code, Codex CLI, Gemini CLI, or OpenCode workflows
  • Review https://github.com/deanpeters/Product-Manager-Skills before adding tam-sam-som-calculator to shared team environments
  • Use tam-sam-som-calculator for development workflows

Works across

Claude CodeCodex CLIGemini CLIOpenCode

Favorites: 0.

Sub-skills: 0.

Aggregator: No.

Original source / Raw SKILL.md

---
name: tam-sam-som-calculator
description: Calculate TAM, SAM, and SOM with explicit assumptions, methods, and caveats. Use when sizing a market for a product idea, business case, or executive review.
intent: >-
  Guide product managers through calculating Total Addressable Market (TAM), Serviceable Available Market (SAM), and Serviceable Obtainable Market (SOM) for a product idea by asking adaptive, contextually relevant questions. Use this to build defensible market size estimates backed by real-world citations, economic projections, and population data—essential for pitching to investors, securing budget, or validating product-market fit.
type: interactive
---


## Purpose
Guide product managers through calculating Total Addressable Market (TAM), Serviceable Available Market (SAM), and Serviceable Obtainable Market (SOM) for a product idea by asking adaptive, contextually relevant questions. Use this to build defensible market size estimates backed by real-world citations, economic projections, and population data—essential for pitching to investors, securing budget, or validating product-market fit.

This is not a back-of-napkin guess—it's a structured, citation-backed analysis that withstands scrutiny.

## Key Concepts

### TAM/SAM/SOM Framework
The three-tier market sizing model:

**Total Addressable Market (TAM):**
- The total market demand for a product or service
- "If we captured 100% of the market, what's the revenue?"
- Broadest possible market (no constraints)

**Serviceable Available Market (SAM):**
- The segment of TAM your company can realistically target
- Narrowed by geography, firmographics, demographics, or product constraints
- "Who can we actually reach with our product?"

**Serviceable Obtainable Market (SOM):**
- The portion of SAM you can realistically capture
- Accounts for competition, market constraints, go-to-market capacity
- "What can we capture in the next 1-3 years?"

### Why This Works
- **Top-down validation:** TAM → SAM → SOM ensures estimates are grounded in reality
- **Investor-friendly:** Standard framework VCs and execs understand
- **Citation-backed:** Real data sources (Census, Statista, World Bank) add credibility
- **Adaptive:** Questions adjust based on context (B2B vs. B2C, US vs. global, etc.)

### Anti-Patterns (What This Is NOT)
- **Not a single-number guess:** "The market is $10B" without supporting data
- **Not static:** Markets evolve—reassess annually
- **Not a substitute for customer validation:** Market size ≠ product-market fit

### When to Use This
- Pitching to investors or execs (need market size in deck)
- Validating product ideas (is the market big enough?)
- Prioritizing product lines (which has bigger opportunity?)
- Setting growth targets (what's realistic to capture?)

### When NOT to Use This
- For internal tools with captive users (no external market)
- Before defining the problem (market sizing requires clear problem space)
- As the only validation (pair with customer research)

---

### Facilitation Source of Truth

Use [`workshop-facilitation`](../workshop-facilitation/SKILL.md) as the default interaction protocol for this skill.

It defines:
- session heads-up + entry mode (Guided, Context dump, Best guess)
- one-question turns with plain-language prompts
- progress labels (for example, Context Qx/8 and Scoring Qx/5)
- interruption handling and pause/resume behavior
- numbered recommendations at decision points
- quick-select numbered response options for regular questions (include `Other (specify)` when useful)

This file defines the domain-specific assessment content. If there is a conflict, follow this file's domain logic.

## Application

Use `template.md` for the full fill-in structure.

This interactive skill asks **up to 4 adaptive questions**, offering **enumerated context-aware options** at each step. The agent adapts questions based on previous responses.

---

### Step 0: Gather Context (Before Questions)

**Agent suggests:**

Before we begin, it's helpful to have product context. If available, please share:

**For Your Own Product:**
- Website copy (homepage, product pages, value prop statements)
- Marketing emails or landing pages
- Product descriptions or positioning statements
- Case studies or customer testimonials
- Sales deck or pitch materials

**If You Don't Have a Product Yet:**
- Find a similar or adjacent product (competitor or analog)
- Copy their website homepage, product description, or landing page
- We'll use this as a reference point for market sizing

**You can paste this content directly, or we can proceed with a brief description.**

**Why this helps:**
- Marketing materials already contain target audience, pain points, and value props
- Analyzing real content (yours or competitors') grounds the analysis in reality
- You can benchmark against similar products' market positioning

---

### Optional Helper Script (Deterministic Math)

If you already have population and ARPU numbers (or a TAM estimate), you can run a deterministic helper to compute TAM/SAM/SOM and generate a Markdown table. This script does **not** fetch data or write files.

```bash
python3 scripts/market-sizing.py --population 5400000 --arpu 1000 --sam-share 30% --som-share 10%
```

---

### Question 1: Problem Space

**Agent asks:**
"Based on the context you've provided (or will describe), what problem space are you exploring for market sizing?"

**Offer 4 enumerated examples (user can select by number or write custom):**

1. **B2B SaaS productivity** — E.g., "Workflow automation for small business operations" (like Zapier, Integromat)
2. **Consumer fintech** — E.g., "Personal budgeting app for Gen Z users" (like Mint, YNAB)
3. **Healthcare/telehealth** — E.g., "Mental health support for remote workers" (like BetterHelp, Talkspace)
4. **E-commerce enablement** — E.g., "Payment processing for online sellers" (like Stripe, Square)

**Or write your own problem space description based on the marketing materials you shared.**

**Tip:** If you provided website copy or marketing materials, the agent can extract the problem space from phrases like:
- "We help [target] solve [problem]"
- "The #1 solution for [use case]"
- Customer pain points in testimonials or case studies

**User response:** [Selection or custom description]

---

### Question 2: Geographic Region

**Agent asks:**
"What geographic region are you targeting?"

**Offer 4 enumerated options (adapted based on problem space):**

1. **United States** — Best for detailed Census Bureau data, BLS stats, robust industry reports
2. **European Union** — Use Eurostat, local statistical agencies; note GDPR/compliance considerations
3. **Global** — World Bank, IMF data; broader but less granular
4. **Specific country/region** — E.g., "Canada," "Southeast Asia," "Latin America"

**Or specify your own region.**

**User response:** [Selection or custom]

**Adaptation logic:**
- If user selected B2B SaaS (Question 1, Option 1) → Emphasize US/EU markets (mature SaaS adoption)
- If user selected Consumer fintech (Question 1, Option 2) → Mention emerging markets (higher mobile adoption)

---

### Question 3: Industry/Market Segments

**Agent asks:**
"What specific industry or market segments does this problem space relate to?"

**Offer 4 enumerated options (adapted based on problem space + geography):**

**Example (if Question 1 = B2B SaaS, Question 2 = US):**
1. **SMB services sector** — 5.4M businesses, $1.2T revenue (US Census, 2023)
2. **Professional services (legal, accounting)** — 1.1M firms, $850B revenue (IBISWorld, 2023)
3. **Healthcare providers** — 900K practices, $4T industry (BLS, 2023)
4. **Tech/software companies** — 500K firms, $1.8T revenue (Statista, 2023)

**Or describe your own industry segment.**

**User response:** [Selection or custom]

**Adaptation logic:**
- If Question 1 = Consumer fintech, offer consumer segments (e.g., "Gen Z 18-25," "Millennials 25-40")
- If Question 1 = Healthcare, offer segments (e.g., "Primary care physicians," "Therapists/counselors")

---

### Question 4: Potential Customers (Demographics/Firmographics)

**Agent asks:**
"Who are the potential customers affected by this problem?"

**Offer 4 enumerated options (adapted based on previous answers):**

**Example (if Question 1 = B2B SaaS, Question 3 = SMB services sector):**
1. **SMBs with 10-50 employees** — 1.2M businesses, $400B revenue (Census Bureau, 2023)
2. **SMBs with 50-250 employees** — 600K businesses, $800B revenue (Census Bureau, 2023)
3. **Solo entrepreneurs/freelancers** — 3.5M self-employed, $200B revenue (BLS, 2023)
4. **Service businesses with online presence** — 2M businesses, $600B e-commerce (Statista, 2023)

**Or describe your own customer segment (firmographics, demographics, income, etc.).**

**User response:** [Selection or custom]

---

### Output: Generate TAM/SAM/SOM Analysis

After collecting responses, the agent generates a structured analysis:

```markdown
# TAM/SAM/SOM Analysis

**Problem Space:** [User's input from Question 1]
**Geographic Region:** [User's input from Question 2]
**Industry/Market Segments:** [User's input from Question 3]
**Potential Customers:** [User's input from Question 4]

---

## Total Addressable Market (TAM)

**Definition:** The total market demand if you captured 100% of potential customers in the problem space.

**Population Estimate:** [Calculated from data sources]
- **Source:** [Citation, e.g., "US Census Bureau, 2023"]
- **Calculation:** [Show math, e.g., "5.4M SMBs × $1.2T revenue = $1.2T TAM"]

**Market Size Estimate:** $[X] billion/million
- **Source:** [Industry report citation]
- **URL:** [Clickable link to source]

---

## Serviceable Available Market (SAM)

**Definition:** The segment of TAM you can realistically target with your product (narrowed by geography, firmographics, product fit).

**Segment of TAM:** [User's narrowed segment from Question 4]

**Population Estimate:** [Calculated]
- **Source:** [Citation]
- **Calculation:** [Show math, e.g., "1.2M SMBs with 10-50 employees"]

**Market Size Estimate:** $[X] billion/million
- **Source:** [Citation]
- **URL:** [Link]

**Assumptions:**
- [List key assumptions, e.g., "Assumes 50% of SMBs have budget for automation tools"]

---

## Serviceable Obtainable Market (SOM)

**Definition:** The portion of SAM you can realistically capture in the next 1-3 years, accounting for competition and market constraints.

**Realistically Capturable Market:** [Agent's estimation based on market maturity, competition]

**Population Estimate:** [Calculated]
- **Source:** [Citation]
- **Calculation:** [Show math, e.g., "1.2M SMBs × 5% market share (Year 1) = 60K customers"]

**Market Size Estimate:** $[X] million
- **Assumptions:**
  - [Competition assumption, e.g., "5 major competitors, market leader has 15% share"]
  - [GTM assumption, e.g., "Sales capacity: 50 customers/month in Year 1"]
  - [Conversion assumption, e.g., "10% trial-to-paid conversion"]

**Year 1-3 Projections:**
- **Year 1:** [X]K customers, $[X]M revenue (5% of SAM)
- **Year 2:** [X]K customers, $[X]M revenue (10% of SAM)
- **Year 3:** [X]K customers, $[X]M revenue (15% of SAM)

---

## Data Sources & Citations

- [Source 1: e.g., "US Census Bureau (2023). County Business Patterns. URL: census.gov"]
- [Source 2: e.g., "IBISWorld (2023). Professional Services Industry Report. URL: ibisworld.com"]
- [Source 3: e.g., "Statista (2023). SMB Software Market Size. URL: statista.com"]
- [Add all sources used]

---

## Validation Questions

1. **Does TAM align with industry reports?** [Compare to 3rd-party market research]
2. **Is SAM realistically serviceable?** [Can your GTM motion reach this segment?]
3. **Is SOM achievable given competition?** [Is 5-15% market share realistic in 3 years?]

---

## Next Steps

1. **Validate with customer interviews:** Does the problem resonate with target segment?
2. **Benchmark against competitors:** What market share do incumbents have?
3. **Refine SOM based on GTM capacity:** Can sales/marketing support this growth?
4. **Update annually:** Markets shift—reassess TAM/SAM/SOM yearly

---

**Would you like to refine any assumptions or explore a different segment?**
```

---

## Examples

See `examples/sample.md` for a full TAM/SAM/SOM analysis example.

Mini example excerpt:

```markdown
**TAM:** 5.4M SMBs × $2,000 ARPA = $10.8B
**SAM:** 1.2M SMBs × $2,000 ARPA = $2.4B
**SOM:** 5% of SAM = $120M
```

## Common Pitfalls

### Pitfall 1: TAM Without Citations
**Symptom:** "The market is $50B" (no source)

**Consequence:** Can't defend the number to investors or execs.

**Fix:** Cite industry reports (Gartner, IBISWorld, Statista) with URLs.

---

### Pitfall 2: SOM Equals SAM
**Symptom:** "SAM is $5B, SOM is $5B" (assuming 100% capture)

**Consequence:** Unrealistic projection—no market has zero competition.

**Fix:** SOM should be 1-20% of SAM in Year 1-3, accounting for competition.

---

### Pitfall 3: No Population Estimates
**Symptom:** Only dollar amounts, no customer counts

**Consequence:** Can't build sales/marketing plans without knowing customer volume.

**Fix:** Always include population (e.g., "1.2M businesses" or "60K customers in Year 1").

---

### Pitfall 4: Static Assumptions
**Symptom:** TAM/SAM/SOM calculated once, never updated

**Consequence:** Stale data as markets shift.

**Fix:** Reassess annually. Markets grow/shrink, competition changes, new data emerges.

---

### Pitfall 5: Ignoring GTM Constraints
**Symptom:** "SOM is 50% of SAM in Year 1" (but no sales team)

**Consequence:** SOM isn't realistic given GTM capacity.

**Fix:** Ground SOM in GTM constraints (sales capacity, marketing budget, conversion rates).

---

## References

### Related Skills
- `skills/positioning-statement/SKILL.md` — TAM/SAM/SOM informs "For [target]" segment size
- `skills/problem-statement/SKILL.md` — Problem space defines the market
- `skills/recommendation-canvas/SKILL.md` — Market sizing informs business outcome projections

### Optional Helpers
- `skills/tam-sam-som-calculator/scripts/market-sizing.py` — Deterministic TAM/SAM/SOM calculator (no network access)

### External Frameworks
- Steve Blank, *The Four Steps to the Epiphany* (2005) — Market sizing for startups
- Lean Startup methodology — Validate market size with experiments, not just desk research

### Data Sources (For Citations)
- **US:** US Census Bureau, Bureau of Labor Statistics, IBISWorld, Statista
- **Europe:** Eurostat, local statistical agencies
- **Global:** World Bank, IMF, Gartner, Forrester

### Dean's Work
- TAM/SAM/SOM Prompt Generator (multi-turn adaptive market sizing)

---

**Skill type:** Interactive
**Suggested filename:** `tam-sam-som-calculator.md`
**Suggested placement:** `/skills/interactive/`
**Dependencies:** None (standalone interactive skill)


---

## Referenced Files

> The following files are referenced in this skill and included for context.

### ../workshop-facilitation/SKILL.md

```markdown
---
name: workshop-facilitation
description: Facilitate workshop sessions in a one-step, multi-turn flow. Use when an interactive skill needs consistent pacing, options, and progress tracking.
intent: >-
  Provide the canonical facilitation pattern for interactive skills: one step at a time, with clear progress, adaptive recommendations at decision points, and predictable interruption handling.
type: interactive
theme: workshops-facilitation
best_for:
  - "Adding structured facilitation to any PM workshop or guided session"
  - "Running interactive sessions with numbered recommendations and progress tracking"
  - "Ensuring your workshops stay on track and end with actionable choices"
scenarios:
  - "I want to run a structured positioning workshop with my product team — set up the facilitation protocol"
  - "Help me facilitate a discovery sprint kickoff with clear questions, options, and progress labels"
estimated_time: "varies by workshop"
---

## Purpose
Provide the canonical facilitation pattern for interactive skills: one step at a time, with clear progress, adaptive recommendations at decision points, and predictable interruption handling.

## Key Concepts
- **One-step-at-a-time:** Ask a single targeted question per turn.
- **Session heads-up + entry mode:** Start by setting expectations and offering `Guided`, `Context dump`, or `Best guess` mode.
- **Progress visibility:** Show user-facing progress labels like `Context Qx/8` and `Scoring Qx/5`.
- **Decision-point recommendations:** Use enumerated options only when a choice is needed, not after every answer.
- **Quick-select response options:** For regular context/scoring questions, provide concise numbered answer options plus `Other (specify)` when useful.
- **Flexible selection parsing:** Accept `#1`, `1`, `1 and 3`, `1,3`, or custom text, then synthesize multi-select choices.
- **Context-aware progression:** Build on previous answers and avoid re-asking resolved questions.
- **Interruption-safe flow:** Answer meta questions directly (for example, "how many left?"), restate status, then resume.
- **Fast path:** If the user requests a single-shot output, skip multi-turn facilitation and deliver a condensed result.

## Application
1. Start with a brief heads-up on estimated time and number of questions.
2. Ask the user to choose an entry mode:
   - `1` Guided mode (one question at a time)
   - `2` Context dump (paste known context; skip redundancies)
   - `3` Best guess mode (infer missing details and label assumptions)
3. Run one question per turn and wait for an answer before continuing.
4. Keep questions plain-language; include a short example response format when helpful.
5. Show progress each turn:
   - `Context Qx/8` during context collection
   - `Scoring Qx/5` during assessment/scoring
6. Ask follow-up clarifications only when they materially improve recommendation quality.
7. For regular context/scoring questions, offer quick-select numbered response options when practical:
   - Keep options concise and mutually exclusive when possible.
   - Include `Other (specify)` if likely answers are open-ended.
   - Accept multi-select responses like `1,3` or `1 and 3`.
8. Provide numbered recommendations only at decision points:
   - after context synthesis,
   - after maturity/profile synthesis,
   - during priority/action-plan selection.
9. Accept numeric or custom choices, synthesize multi-select choices, and continue.
10. If interrupted by a meta question, answer directly, then restate progress and pending question.
11. If the user says stop/pause, halt immediately and wait for explicit resume.
12. End with a clear summary, decisions made, and (if best guess mode was used) an `Assumptions to Validate` list.

## Examples
**Opening:**
"Quick heads-up: this should take about 7-10 minutes and around 10 questions. How do you want to start?
1. Guided mode
2. Context dump
3. Best guess mode"

**User:** "2"

**Facilitator:** "Paste what you already know. I’ll skip answered areas and ask only what’s missing."

**Decision point after synthesis:**
1. **Prioritize Context Design** (Recommended)
2. Prioritize Agent Orchestration
3. Prioritize Team-AI Facilitation

**User:** "1 and 3"

**Facilitator:** "Great. We’ll run Context Design first, with Team-AI Facilitation in parallel."

## Common Pitfalls
- Asking multiple questions in the same turn.
- Offering recommendations after every answer (creates interaction drag).
- Using shorthand labels without plain-language questions.
- Hiding progress, so users don't know how much remains.
- Ignoring the user's chosen option or custom direction.
- Failing to label assumptions when running in best-guess mode.

## References
- Use as the source of truth for interactive facilitation behavior.
- Apply alongside workshop skills in `skills/*-workshop/SKILL.md` and advisor-style interactive skills.

```

### scripts/market-sizing.py

```python
#!/usr/bin/env python3
"""Deterministic TAM/SAM/SOM calculator.

No network access. Prints a Markdown summary to stdout.
"""

import argparse
import sys


def parse_share(value: str) -> float:
    raw = value.strip()
    if raw.endswith("%"):
        raw = raw[:-1]
        return float(raw) / 100.0
    return float(raw)


def format_money(value: float, currency: str) -> str:
    rounded = round(value, 2)
    formatted = f"{rounded:,.2f}"
    if formatted.endswith(".00"):
        formatted = formatted[:-3]
    return f"{currency}{formatted}"


def parse_args() -> argparse.Namespace:
    parser = argparse.ArgumentParser(
        description="Calculate TAM/SAM/SOM from population and ARPU or a TAM value.",
    )
    basis = parser.add_mutually_exclusive_group(required=True)
    basis.add_argument("--tam", type=float, help="Total Addressable Market value.")
    basis.add_argument("--population", type=float, help="Total potential customers.")

    parser.add_argument("--arpu", type=float, help="Annual revenue per customer.")
    parser.add_argument("--sam-share", required=True, help="SAM share of TAM (0-1 or 0-100%).")
    parser.add_argument("--som-share", required=True, help="SOM share of SAM (0-1 or 0-100%).")
    parser.add_argument("--currency", default="$", help="Currency symbol prefix (default: $).")

    args = parser.parse_args()
    if args.population is not None and args.arpu is None:
        parser.error("--arpu is required when using --population")
    return args


def validate_share(name: str, value: float) -> None:
    if value <= 0 or value >= 1:
        raise ValueError(f"{name} must be between 0 and 1 (exclusive).")


def main() -> int:
    try:
        args = parse_args()
        sam_share = parse_share(args.sam_share)
        som_share = parse_share(args.som_share)
        validate_share("sam-share", sam_share)
        validate_share("som-share", som_share)

        if args.tam is not None:
            tam = args.tam
            basis = f"TAM input: {format_money(tam, args.currency)}"
        else:
            tam = args.population * args.arpu
            basis = (
                f"Population x ARPU: {args.population:,.0f} x "
                f"{format_money(args.arpu, args.currency)}"
            )

        sam = tam * sam_share
        som = sam * som_share

        print("# Market Size Summary\n")
        print("Inputs:")
        print(f"- {basis}")
        print(f"- SAM share of TAM: {sam_share:.0%}")
        print(f"- SOM share of SAM: {som_share:.0%}\n")
        print("| Metric | Formula | Estimate |")
        print("| --- | --- | --- |")
        print(
            f"| TAM | {basis} | {format_money(tam, args.currency)} |"
        )
        print(
            f"| SAM | TAM x {sam_share:.0%} | {format_money(sam, args.currency)} |"
        )
        print(
            f"| SOM | SAM x {som_share:.0%} | {format_money(som, args.currency)} |"
        )
        return 0
    except (ValueError, argparse.ArgumentError) as exc:
        print(f"Error: {exc}", file=sys.stderr)
        return 1


if __name__ == "__main__":
    raise SystemExit(main())

```

### examples/sample.md

```markdown
# TAM/SAM/SOM Examples

### Example 1: Good TAM/SAM/SOM Analysis (B2B SaaS Workflow Automation)

**Step 0 - Context Provided:**
User shares Zapier's homepage copy:
> "Zapier connects your apps and automates workflows. Easy automation for busy people. Move info between your web apps automatically, so you can focus on your most important work."

**Question 1 Response:** "B2B SaaS productivity — Workflow automation for small business operations" (extracted from "automates workflows" and "busy people")
**Question 2 Response:** "United States"
**Question 3 Response:** "SMB services sector"
**Question 4 Response:** "SMBs with 10-50 employees"

---

**Generated Analysis:**

```markdown
# TAM/SAM/SOM Analysis: Workflow Automation for SMBs

**Problem Space:** Workflow automation for small business operations
**Geographic Region:** United States
**Industry/Market Segments:** SMB services sector
**Potential Customers:** SMBs with 10-50 employees

---

## Total Addressable Market (TAM)

**Definition:** Total US market for workflow automation tools across all business sizes.

**Population Estimate:** 33.2M businesses (US Census Bureau, 2023)

**Market Size Estimate:** $50B
- **Source:** Gartner, "Business Process Automation Market, 2023"
- **URL:** [gartner.com/business-automation-report]
- **Breakdown:** $30B (large enterprise), $15B (mid-market), $5B (SMB)

---

## Serviceable Available Market (SAM)

**Definition:** US SMBs (10-50 employees) in services sector that could use workflow automation.

**Segment of TAM:** SMBs with 10-50 employees in services sector

**Population Estimate:** 1.2M businesses
- **Source:** US Census Bureau, "County Business Patterns, 2023"
- **URL:** [census.gov/cbp]
- **Calculation:** 5.4M total SMBs × 22% (10-50 employee size) = 1.2M

**Market Size Estimate:** $3.6B
- **Source:** IBISWorld, "SMB Software Market, 2023"
- **Calculation:** 1.2M businesses × $3,000 avg spend/year = $3.6B
- **URL:** [ibisworld.com/smb-software]

**Assumptions:**
- 50% of SMBs have budget for automation tools ($1.8B addressable)
- Avg $3,000/year spend on software (Statista, 2023)

---

## Serviceable Obtainable Market (SOM)

**Definition:** Market share we can realistically capture in next 3 years.

**Realistically Capturable Market:** 5-15% of SAM over 3 years

**Year 1 Population Estimate:** 12K customers (1% of SAM)
- **Calculation:** 1.2M businesses × 1% = 12K
- **Revenue:** $36M (12K × $3,000 ARPU)

**Year 3 Population Estimate:** 180K customers (15% of SAM)
- **Calculation:** 1.2M businesses × 15% = 180K
- **Revenue:** $540M (180K × $3,000 ARPU)

**Assumptions:**
- **Competition:** 5 major players (Zapier 20% share, Integromat 10%, others <5%)
- **GTM Capacity:** PLG motion, 1K trial signups/month in Year 1, scaling to 15K/month by Year 3
- **Conversion:** 10% trial-to-paid conversion
- **Churn:** 15% annual churn (industry standard for SMB SaaS)

**Year 1-3 Projections:**
- **Year 1:** 12K customers, $36M revenue (1% of SAM)
- **Year 2:** 60K customers, $180M revenue (5% of SAM)
- **Year 3:** 180K customers, $540M revenue (15% of SAM)

---

## Data Sources & Citations

- US Census Bureau (2023). County Business Patterns. [census.gov/cbp]
- Gartner (2023). Business Process Automation Market Report. [gartner.com]
- IBISWorld (2023). SMB Software Market Analysis. [ibisworld.com]
- Statista (2023). SMB Software Spending. [statista.com]

---

## Validation Questions

1. **Does TAM align with industry reports?** ✅ Yes—Gartner estimates $50B total BPA market
2. **Is SAM realistically serviceable?** ✅ Yes—PLG motion can reach 1.2M SMBs via digital marketing
3. **Is SOM achievable given competition?** ⚠️ Stretch goal—Zapier has 20% share; 15% in Year 3 requires strong differentiation

---

## Next Steps

1. **Validate with 20 customer interviews:** Confirm $3K/year budget exists
2. **Benchmark against Zapier/Integromat:** Study their GTM, pricing, churn
3. **Refine SOM based on pilot:** Run 6-month pilot, measure actual conversion/churn
4. **Reassess annually:** SMB market growing 5%/year—update TAM/SAM annually
```

**Why this works:**
- Citations for every data point (Census, Gartner, IBISWorld, Statista)
- Shows math and assumptions transparently
- Realistic SOM (1% → 5% → 15% over 3 years)
- Identifies validation gaps ("⚠️ Stretch goal")

---

### Example 2: Bad TAM/SAM/SOM Analysis (No Citations, Vague)

```markdown
# TAM/SAM/SOM Analysis: Productivity Tool

**TAM:** The productivity market is huge, probably $100 billion.

**SAM:** We're targeting small businesses, so maybe $10 billion.

**SOM:** We think we can get 1% in the first year, so $100 million.
```

**Why this fails:**
- No citations (where did "$100B" come from?)
- Vague segments ("small businesses" = how many? what size?)
- No assumptions documented (1% of SAM—why?)
- No population estimates (how many customers?)
- No validation questions or next steps

---

```

tam-sam-som-calculator | SkillHub