Tax
Tax assistant: import your transactions
Export your transactions from your exchange or broker and import the CSV file here. The assistant detects the columns, calculates realised gains using FIFO and turns the result into an overview per filing section for the Netherlands (box 3) or Belgium. Your file stays in your browser: nothing is uploaded or stored.
Choose your transaction file (CSV)
Export transactions from your exchange or broker and pick the CSV file. Column names are detected automatically.
No file loaded yet.
Your file stays in your browser. Nothing is uploaded, stored or shared.
Overview per filing section
- Realised gain
- € 0,0000
- Sales proceeds
- € 0,0000
- Cost basis of open positions
- € 0,0000
- Estimated box 3 tax
- € 0,0000
This is a tool, not tax advice. Always verify the result against your own records or with an accountant.
Share this scenario
The link contains every value you entered, so you can revisit or share the calculation.
Frequently asked questions
- Is my file uploaded?
- No. Parsing and calculation happen entirely in your browser. No transaction data reaches our servers or database.
- Which exports work?
- Most CSV exports from exchanges and brokers. Column names such as date, type, asset, quantity, amount and fee are detected in English and Dutch.
- What is free?
- Up to 50 transactions is free. With Block #9 Pro you process a full year at once.
- Is this tax advice?
- No. It is a tool to prepare your filing. Verify the result against your own records or with an accountant.
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