Overview

capi.tax helps you turn the trade data from your US broker into figures you can use for your German tax return. If you invest through Interactive Brokers or Tastytrade, your broker reports everything in US dollars and follows US rules. The German Finanzamt needs the same activity in euros, following German rules. capi.tax bridges that gap for you.

What it does

You give capi.tax the CSV export from your broker. It reads each trade, converts every amount into euros using official Deutsche Bundesbank exchange rates, and applies the rules German tax law expects, including the FIFO method for matching purchases to sales. The result is a clear summary and the values you need for your Anlage KAP.

It also separates your activity into the right tax categories, applies the Teilfreistellung where it belongs (for example on equity funds), and keeps track of gains and losses in the correct loss pools.

Who it is for

capi.tax is for ordinary private investors in Germany who use an international broker and want a calm, organised starting point for their tax return. You do not need any tax or technical knowledge to use it.

What you need

  • A transaction export in CSV format from Interactive Brokers or Tastytrade
  • A current web browser

Your data stays with you

Everything runs locally in your browser. Your transactions are never uploaded to a server and are not stored anywhere. When you close the page, the data is gone. This means your financial details stay on your own computer from start to finish.

capi.tax prepares your data; it is not tax advice. Please review the figures and ask a tax advisor (Steuerberater) about your personal situation.

No tax advice - data preparation only — This tool is solely for preparing your transaction data and does not constitute tax advice. Calculations are performed automatically and without any warranty as to their accuracy, completeness or timeliness. Use is at your own risk; you alone are responsible for the correctness of your tax return. Verify all results yourself and consult a tax advisor if in doubt. Liability for any damages arising from use is excluded to the extent permitted by law.

Modern tax preparation
for German investors

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  • Your data stays local
  • GDPR compliant
  • No tax advice

© 2026 capi.tax – Data preparation tool. This is not tax advice. Consult a tax advisor for questions.