Model a Dutch tax structure the way you explain it.

Describe the case in plain language. The structure appears on a canvas — entities, flows, taxes, net result — computed deterministically against the 2026 rules, with a check on every number that can go wrong.

No account. Nothing to install. Your document gets its own link.

The spreadsheet knows. Nobody else does.

Every adviser has the file. Three sheets, colour-coded, one rate hardcoded two years ago. It answers exactly one question, for exactly one client, and only the person who built it can be sure it is still right. The memo that goes to the client is typed separately — so when the client asks “and what if we add a holding?”, both have to be rebuilt.

The structure is the thing you are reasoning about. It should be an object you can edit, not an implicit layout of cells.

Three steps

1 · Describe the case

Type it the way you would explain it to a colleague: client has a BV, takes €62k salary, wants to add a holding. Dutch or English, prose, no form to fill in.

2 · Watch it compute

Entities, flows and taxes appear on the canvas and settle into numbers. Drag a value and everything downstream moves with it.

3 · See what breaks

Checks run against the published 2026 norms — a salary under the gebruikelijk loon, a deduction claimed without the urencriterium — and each one names the norm it came from.

The model draws. The engine calculates.

A language model reads your description and produces structure: entities, flows, anchors. It never produces an amount. Every euro on the canvas comes from a rule pack — box 1, box 2, vennootschapsbelasting, Zvw and the heffingskortingen, applied in one fixed order. The same rule pack drives every calculator on this site, so two pages cannot disagree with each other.

Rates and norms come from the published 2026 figures, each carrying its source. All figures & sources →

Worked examples

Public, pre-built cases: the same engine, fixed to a single question. These pages are in Dutch.

All calculators →

What is not there yet

The editor is open and free to use. These are the pieces still being built. Leave your address and you get one mail when one of them lands.

  • holding structures
  • fiscal partner
  • 30% ruling in the editor
  • scenario comparison
  • export for the client file
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Start with one client case.

Describe it in a sentence and see what the structure actually costs.

Open the editor →