Portfolio Optimizer vs SEC EDGAR Data

Portfolio Optimizer is a free, no-signup Web API implementing modern-portfolio-theory algorithms — mean-variance and minimum-variance optimization, risk and performance analytics, backtesting, and factor-model tools — over JSON, so it can be called from Python, Excel, Google Sheets, or any HTTP client without an SDK. The homepage explicitly advertises free access with no registration required, and a live test against a real optimization endpoint (api.portfoliooptimizer.io) returned `Access-Control-Allow-Origin: *` on both a route-not-found and a malformed-payload response, confirming CORS is enabled; the same responses carry a `WWW-Authenticate: Key` header hinting at an optional key for higher throughput, though the observed default rate limit is a modest 1 request/second.

SEC EDGAR's data.sec.gov REST APIs serve JSON-formatted company filing histories and XBRL financial-statement facts (10-K, 10-Q, 8-K, and more) extracted from filings submitted to the U.S. Securities and Exchange Commission. No authentication or API key is required, but the SEC's fair-access policy requires a descriptive User-Agent header identifying the requester and caps traffic at 10 requests per second — requests without one are rejected with a 403. A live probe confirmed CORS is enabled (Access-Control-Allow-Origin: *) once that header is set.