ABOUT
Clear calculations, narrow claims.
Operated under the Sumlucid brand, this independent calculator website helps explain saving, fee and stock-return scenarios.
One tool for each question
The five calculators cover compound interest, savings goals, investment fees, stock profit and foreign-stock returns. You choose the assumptions and see a result, chart, worked example and model limitations.
Created and maintained under the Sumlucid brand
Sumlucid is the project's public name, not a financial credential. The site uses deterministic formulas, decimal arithmetic and tests against examples and edge cases. Errors remain possible: results should be inspectable.
See the calculation methodology and change history.
Independence and limits
Sumlucid is not a bank, broker or financial, tax or legal advisory service. It is not affiliated with the ECB, Google or any security issuer. Cloudflare provides hosting, not an endorsement of our calculations. No security, broker or return is recommended or guaranteed.
Privacy and corrections
No account is needed. Financial amounts stay in your browser. For calculation errors, accessibility, privacy or copyright inquiries, see Contact and corrections.