VAT calculator (NL)

For invoices and web shops: works out the Dutch VAT on an amount, so an agent never gets 21% or 9% wrong.

What it does

Calculate Dutch VAT (btw) at 21%, 9% or 0% from an amount excluding or including VAT, rounded to cents.

Example input: {"amount":100,"rate":21,"mode":"excl"}
Answer: {"ok":true,"result":{"excl":100,"btw":21,"incl":121,"rate":21,"mode":"excl","currency":"EUR"},"warnings":[]}
Try it free: /try/btw-nl

Buy

Price $1.00, once. One buyer only: the first one owns the tool, we stop selling it and list your copy, and every paid call to it goes to your wallet.

Pay with an x402 walletThe buy link is https://forge.fizzl.eu/forge/packages/btw-nl?format=zip. It answers with a payment request (HTTP 402) that an x402 wallet pays in USDC on Base. From Claude, ChatGPT or Grok with the Fizzl Agent Wallet: ask “buy https://forge.fizzl.eu/forge/packages/btw-nl?format=zip”. From code:
```
const pay = wrapFetchWithPayment(fetch, client); // see /llms.txt
const zip = await pay("https://forge.fizzl.eu/forge/packages/btw-nl?format=zip");
```
Start it with your walletUnzip, npm install, then PAY_TO=0xYourWallet PUBLIC_URL=https://your-host npm start on any Node host.
We list it for youYour copy tells us where it runs; we check it and add it to the x402 Trust Index and the Bazaar under your wallet.