Purpose
Turn a rough event concept into a defensible line-item budget — with low/mid/high ranges per category, per-attendee benchmarks, and a contingency reserve — so an event marketer can pressure-test scope, request budget internally, and spot the categories most likely to blow past plan.
When to Use
Invoke this skill when the user asks to:
- Estimate the cost of a conference, trade show, summit, or field event
- Scope a budget for a product launch, customer dinner, or VIP event
- Build a first-pass budget before requesting internal approval
- Compare the cost of two event formats or venue tiers
- Figure out per-attendee cost or what a fixed budget can realistically cover
Inputs Required
Before starting, collect:
- Event type: Conference, trade show booth, product launch, webinar, executive dinner, field/roadshow event, etc.
- Headcount: Expected number of attendees
- Location: City and country (affects venue, F&B, and travel costs)
- Format: In-person / virtual / hybrid
- Duration: Number of days (and half-day vs. full-day)
- Budget ceiling (if any): A fixed cap to design against, or "estimate open"
- Must-haves vs. nice-to-haves: Any non-negotiables (keynote, catering, custom booth, swag)
If duration or format is missing, assume a single-day in-person event and state the assumption. If location is a major metro (NYC, SF, London, Singapore), apply a high-cost-city multiplier and flag it.
Instructions
Step 1: Establish the Cost Basis
Set the anchors the whole estimate depends on:
- Location tier: Tier 1 (high-cost metros: NYC, SF, London, Singapore) → apply +25–40% to venue and F&B; Tier 2 (mid-size cities) → baseline; Tier 3 (secondary/regional) → −15–25%
- Per-attendee reference range for this event type (used to sanity-check the bottom-up total):
- Executive dinner: $250–600/head
- Field/roadshow event: $150–400/head
- Conference (multi-day): $500–1,500/head
- Product launch: $300–900/head
- Trade show booth (per-event, not per-head): $20k–150k depending on booth size
- Webinar/virtual: $15–75/head
- State the chosen basis explicitly before building line items.
Step 2: Build the Category Estimates
For each applicable category, produce a Low / Mid / High range and a one-line cost driver. Skip categories that don't apply to the format (e.g., no venue for virtual).
Venue — Space rental, deposits, permits, insurance.
- Driver: location tier, day count, prestige of space. Typically 20–35% of total for in-person events.
Food & Beverage — Catering, bar, breaks, service charge + gratuity (assume 22–28% added on top).
- Driver: headcount × per-head F&B rate × meal periods. Often the fastest-growing line.
AV & Production — Sound, staging, lighting, screens, recording, live-stream, technicians.
- Driver: room size, stage complexity, whether it's recorded/streamed. Frequently underestimated by 20–40%.
Staffing — Event staff, registration, security, on-site coordinators, agency fees.
- Driver: attendee-to-staff ratio (plan ~1 staffer per 30–50 attendees), plus agency management fee (10–20% of program if used).
Swag & Collateral — Branded gifts, printed signage, badges, lanyards, giveaways.
- Driver: per-head swag tier ($5 basic / $25 mid / $75+ premium) × headcount.
Travel & Accommodation — Speaker, VIP, and internal-team flights and hotels.
- Driver: number of traveling attendees × (flight + nights × room rate). Only include the people the host is paying for.
Marketing & Content — Promotion, design, photography/videography, presentation build.
- Driver: whether creative is in-house or outsourced.
Technology & Tools — Registration platform, event app, virtual platform, badge printing, lead capture.
- Driver: platform per-registrant fees for larger events.
Step 3: Add Contingency and Totals
- Sum all category mids to a base estimate.
- Apply a contingency reserve: 10% for well-scoped repeat events, 15% for first-time or complex events, 20% for events in unfamiliar markets or with heavy production.
- Produce three total lines: Lean total (sum of lows), Realistic total (sum of mids + contingency), Premium total (sum of highs + contingency).
Step 4: Reconcile and Flag
- Compare the Realistic total ÷ headcount against the Step 1 per-attendee reference range. If it falls outside, flag it and explain which category is driving the variance.
- If a budget ceiling was provided, state whether the plan fits, and if not, name the 2–3 categories to cut first (typically swag, premium AV, or F&B tier).
- Flag the top 3 cost-driver risks most likely to push the event over budget.
Output Format
- Structure: Cost basis statement → category table → totals block → reconciliation and flags
- Length: 500–800 words
- Format: A budget table (Category | Low | Mid | High | Cost driver), followed by a totals block and a short prose reconciliation section
- Sections: Cost Basis & Assumptions → Budget by Category (table) → Totals (Lean / Realistic / Premium) → Per-Attendee Check → Top 3 Cost-Driver Flags → Where to Cut First (only if a ceiling was given)
- Tone: Event operations lead — pragmatic, numbers-first, honest about where estimates are soft
Quality Checklist
Before delivering output, verify:
- [ ] Every applicable category has a Low / Mid / High range and a named cost driver
- [ ] Categories that don't apply to the format were correctly excluded (no venue for a webinar)
- [ ] Contingency is applied at the stated percentage and shown as a separate line
- [ ] All three totals (Lean, Realistic, Premium) are calculated and add up correctly
- [ ] The per-attendee check compares against the reference range and flags any variance
- [ ] Assumptions (location tier, duration, format) are stated explicitly where inputs were missing
Notes
- F&B and AV are the two categories most likely to be underestimated — service charges and production labor are the usual culprits.
- These are planning-grade estimates, not vendor quotes. Advise the user to get 2–3 real quotes for venue and AV before locking the number.
- For trade show booths, cost scales with square footage and build complexity far more than with attendee count — treat headcount as a soft input there.
- If the budget ceiling is tight, cutting swag tier and downgrading F&B service style preserves attendee experience better than cutting AV, which is highly visible on stage.
How to use this skill
This file is a Claude Code skill in Anthropic's standard format — markdown with YAML frontmatter at the top.
Installing in Claude Code:
~/.claude/skills/<folder-name>/SKILL.md— auto-loads in every session anywhere on your machine (recommended for skills you'll use across multiple projects)<your-project>/.claude/skills/<folder-name>/SKILL.md— auto-loads only when working in that project (recommended for project-specific skills)
Restart Claude Code or open a new session to register.
Using in Claude.ai, ChatGPT, Gemini, or other AI tools:
- Drag this file into a new chat, or copy and paste its contents
- Send your task or request as your next message — the AI will apply the skill where it fits
For Claude Code skill details: https://docs.anthropic.com/en/docs/claude-code/skills