About Stupidly Clever

Stupidly Clever is a free toolkit of calculators, data tools, and APIs covering personal finance, business analytics, health, global data, and more. Every tool is available as a web page, a documented REST API, and an MCP tool for AI agents — so the same calculation that someone runs manually in a browser can also be called programmatically by a developer or an AI assistant.

Stupidly Clever is built and maintained by Constantine Kakoushis, a former developer and leader with a keen interetst in data, to help teams focus on their project's core rather than focusing on everything else.

Every calculation implements a published formula, a regulatory rule, or an authoritative dataset. Nothing here is proprietary medical, financial or legal advice, and no tool produces a recommendation — they compute a figure and show the inputs and method behind it, so you can check the reasoning rather than take the number on trust.

Health tools state the model they implement and its primary published reference on the page itself, alongside a disclaimer that the result is an educational estimate rather than a clinical diagnosis.

Formulas are implemented from primary sources — regulatory standards, peer-reviewed literature, recognised textbook treatments and official government publications — and are covered by unit tests in the shared calculation package, which is the same code the web tools, the REST API and the MCP tools all run.

Formula sourcing and data sourcing are tracked separately, because a correct formula can still be applied to approximate data. What each dataset actually is, is published at /data-sources, and the editorial policy behind both is set out in the methodology.

Every reference dataset behind the tools is listed at /data-sources with its publisher, vintage, refresh mode and the date it was last verified. That page also states plainly where a dataset is an illustrative estimate approximating a publisher's figures rather than the publisher's own figures — those tools carry the same notice on the page itself, and every API response returns the same information in a provenance field.

The combination of web UI, REST API, and MCP tool server means the same underlying calculation is available to someone filling in a form, a developer building a product, or an AI agent doing research or financial modelling. The API is documented at /docs and can be accessed with a free API key.

If you find a calculation error, an outdated data source, or a factual inaccuracy, report it via the support page. Include the tool URL and what you believe is incorrect. We aim to respond within 5 business days. Confirmed errors are corrected and the page's lastmod date is updated in the sitemap.