IndieBrokenLinks exists because a link check should end in a repair list, not another score to interpret. Paste one public page URL and it reads the HTML that the server returns. It finds the first 200 unique web links in page order, checks their live responses, and moves definite failures to the top.
The distinction matters. HTTP 404 and 410 say a destination is gone, so those links are marked broken. A successful response reached through redirects is shown separately. A timeout, block, or ambiguous status stays under could not verify. IndieBrokenLinks does not turn uncertainty into a false failure.
The checker reads at most 1 MB of server-returned HTML. It does not run page JavaScript or crawl a whole site. The 200-link cap keeps a single check useful and bounded. If the page contains more, the result says so plainly.
The source is the page you submit and the live HTTP responses, interpreted using HTTP Semantics, RFC 9110. Nothing you check becomes a public listing. There is no account, card, premium plan, or upgrade nag.