Event Impact Calculator · for host cities and event organisers
The report says 25 million. How much of it stayed?
An online calculator that estimates what a major event is really worth to its host economy. Twelve guided steps take you from gross spending to the money that stays in the city, with every assumption visible.
Free demo: no account, no card · Full licence €997 a year + VAT where applicable, 7 days free
01 / The problem
The headline number is the easy part.
The city needs an impact figure before it approves the bid. The funder wants one before it commits. The organiser needs one before ticket sales, hotel nights and partner budgets are known.
So the estimate starts from assumptions. That part is normal.
The trouble starts later, when someone in the council meeting asks one question.
Most impact numbers count the money that flows through a city. Not the money that stays in it.
Jesse Kiuru, Host City Strategy
02 / Where the money goes
Why the big number shrinks when you look closer.
A lot of event spending was never new to the city, or leaves it again within days. An honest estimate takes these out, one by one.
Locals spending at home
A resident who buys a festival ticket would have spent that money in the city anyway.
Money spent elsewhere
The flight, the train and the hotel two towns away happen outside your economy.
Tax that leaves
VAT goes to the state, not to the businesses in your city.
Money counted twice
A ticket is income for the organiser and spending for the visitor. It is one euro, not two.
Chains and platforms
Booking fees, franchise payments and outside owners take their share before the money settles.
Suppliers from outside
Local businesses pay their own non-local costs. That part leaves too.
03 / The real question
How much stayed?
The first question gives you a big number for the press release. The second one tells the city what the event actually does for local businesses, jobs and the tax base.
The Event Impact Calculator is built to answer the second question, and to show how it got there.
04 / What you get
Three figures, each stricter than the last.
Instead of one inflated headline, the calculator gives you three numbers. Each one has a clear definition, so everyone in the room reads it the same way.
Illustration.
The total scale of event-linked activity: visitors, organiser and stakeholders, with internal transfers counted once.
The new money that enters the host economy because the event happens, after locals, out-of-area spending, VAT and leakage are removed.
The share of that new money that stays after local businesses pay their non-local costs. The figure cities and funders actually care about.
A 16-day city festival, all twelve steps completed.
05 / How it works
From assumption to estimate, in twelve guided steps.
Each step has a short guide and expert defaults. You need numbers you can explain, not perfect data.
- Event info
- Visitor groups
- Spending streams
- Accommodation
- Spending data
- Gross spend
- Direct impact
- Organiser spend
- Partner inflows
- Net impact
- Local retention
- Summary and reports
Start without perfect data
Built-in VAT, leakage and retention starting points, with tax profiles for Belgium, Finland, Germany, France, the UK, Sweden, Norway, Estonia and the US (Illinois). Override any of them.
Catch your own mistakes
Six consistency checks test your inputs against each other and flag the ones that contradict.
Show the path
The model tracks which values are expert defaults and which are yours. When the questions come, the full logic is on the page.
06 / One model, every phase
Build it once. Keep it all the way.
The same estimate carries the number from the first forecast to the final result. No rebuilding when the plan changes.
Test the opportunity
Sharpen the estimate
Report the result
07 / Inside the app
The summary writes itself from your numbers.
Step 12 turns the estimate into a one-page executive summary for decision-makers. Export it to PDF or Word, or copy the text into your own template.
- Executive summary written from your results: what the event triggers, what counts, what stays.
- Full impact report with every assumption and deduction documented, as a PDF.
- Assumption trail: expert defaults and your own values, tracked automatically.
- Unlimited events and scenarios. Duplicate an estimate to test a variation without losing the original.
- Three finished templates: a continental championships, a city festival and an association congress.
Free. No account, no card. We email you a personal link that keeps working.
08 / Where it fits
You should not need a study for every scenario.
A full independent study has its place for the very largest events. The calculator is how you get there with your assumptions structured, not scattered.
| Option | Good for | What it misses |
|---|---|---|
| Another spreadsheet | A quick start | Formulas get hard to follow, versions multiply and the logic sits with one person |
| A commissioned study | An independent report | Expensive, and too slow to test every bid, funding case and plan change |
| Event Impact Calculator | A transparent model your team builds, updates and explains itself | Start with what you know today. Improve it as the event develops. |
09 / Who built it
Built to answer the question in the room.
I have sat on both sides of this in Lahti. On the city side, and inside the city's event company. Every time an impact number went into a bid or a funding paper, someone eventually asked how we got there.
So I built a model that answers that question by design. Direct effects only. No multipliers. Every deduction on the page, so the number can be checked by anyone who asks.
No logos or testimonials here. Open the three finished events instead and check every step, number and deduction yourself.
Jesse Kiuru · jessekiuru.com · LinkedIn
10 / Price
Test it first. Then estimate your own event.
Start with the free demo. When you are ready to model your own event, the 7-day trial gives your team the full calculator.
- Leave your name and emailWe send you a personal link. It keeps working, so you can come back later.
- Open three finished eventsA championships, a festival and a congress, all twelve steps complete.
- Change any numberWatch every figure update, down to what stays local.
- The full 12-step calculator
- Unlimited events and scenarios
- 5 users: you plus 4 colleagues, each with their own login
- Three finished templates to start from
- Country tax profiles, VAT, leakage and retention defaults
- Executive summary and full report, PDF and Word
- Free updates and email support for the licence year
Card at checkout. Nothing is charged for 7 days. Renews at €997 a year. Invoicing or procurement questions: jesse@bonacube.com
11 / Questions
Asked before starting
Why is the estimate smaller than other impact studies?
Because it only contains money you can trace. The model reports direct, first-round effects: no multipliers, no indirect or induced effects, internal transfers counted once, and local public funding not counted as new money. A smaller number you can defend is worth more than a bigger one you cannot.
We do not have perfect data. Can we still use it?
Yes, that is the normal case. You start from forecasts and assumptions, supported by expert defaults for VAT, leakage and spending behaviour. The model tracks which values are defaults and which are yours, and the estimate updates as better information arrives.
Does it work for our type of event?
The model works for sport, culture and business events. The three templates cover a continental championships, a city festival and an association congress. Visitor groups, spending streams and stakeholders are fully configurable.
Does the calculator decide what our impact is?
No. It structures the estimate and applies consistent rules. You own the assumptions, and the built-in checks tell you when they contradict each other.
How does the free demo work?
Leave your name and email on the demo page and we send you a personal link to three finished estimates. No account, no card, and nothing you change is saved.
How does the free trial work?
Create your login, then start the trial at checkout. Nothing is charged for 7 days. After that the licence renews at €997 a year.
How many people can use one licence?
Five: you and up to four colleagues from your organisation, each with their own login.
Can I export the reports?
Yes. The executive summary exports to Word and PDF and copies as plain text. The full report documents every assumption as a PDF.
Who can see our calculations?
Only your team. Your estimates are stored privately in your own account, and you can export everything at any time.
Before the number goes into the bid, the funding paper or the press release
Find out what stays, before someone else asks.
Open three finished events for free. Change a number and watch the three figures move. Then decide if you want to run your own.
Free demo: no account, no card · Licence €997 a year + VAT where applicable