How we check links

Our promise is short: every link on odd-sites.com is checked once a day. This page explains what that does and does not mean, so you can judge for yourself how much to trust a badge.

What we check

Each night an automated checker visits the landing URL of every site and records what happens. It looks at:

1. Whether the domain resolves and the certificate is valid. We also note certificates that are about to expire.
2. The HTTP status. We try a lightweight request first and fall back to a full page request if the site rejects it, because some perfectly healthy sites answer the lightweight one with an error.
3. Redirects. A site that redirects within its own domain is fine. If the redirect lands on a different domain, or on an advertising or parking host, we flag it. Classic sites sometimes end up redirecting somewhere unrelated after a sale or a rebrand.
4. Parked or for-sale domains. We look for known parking hosts and typical for-sale wording.
5. Hijacked pages. We look for signs that a domain has been taken over, such as gambling, adult, pharmacy or crypto content, or a sudden change of language or page type.
6. Large content changes. We keep a simple fingerprint of the page title and the opening text. If a stable domain changes dramatically, a person reviews it.
7. Quota and rate-limit errors, such as "bandwidth exceeded" messages and CDN origin errors.

We are polite about it: one request per host per second, with an honest user agent.

Bot walls: alive but unverifiable

Some sites sit behind a bot-protection screen (the "Just a moment..." kind). Our checker cannot get past it, and neither can most other automated tools. We do not treat that as a failure. These sites are marked alive, but unverifiable by the daily check, and they are queued for a weekly check in a real browser that loads the page and confirms the title and content. A handful of sites that are fully built in JavaScript get the same treatment.

What the badges mean

• Verified alive: the last check succeeded. We show how long ago.
• Checks blocked by site (alive): the site is up but a bot wall blocks our checker.
• Degraded: one or two checks have failed. We are watching it.
• Resting: the site has failed several checks in a row, or is showing a temporary problem such as a quota message. It may come back. We keep retrying, first hourly and then daily.
• Rest in peace: the site is gone. This happens after a week of failures, or immediately when we confirm that a domain is parked, for sale or hijacked.

Resting and rest in peace

A resting site is one that is asleep, not dead. Small projects often run out of bandwidth, hit a hosting quota or fall over during a surge, and recover in hours. We keep the page, show the badge, and keep trying.

A site that is resting in peace is gone for good, or has been taken over by something that is not the site anymore. It is removed from the random button, the lists and the sitemap. We keep a short memorial page for it with what it was, and a link to an archived copy in the Wayback Machine where one exists. Sometimes a rest-in-peace site comes back, and then we are delighted to revive it.

Every change of state is also sent to a person for review.

What link checks cannot do

• They are not a security audit. We check that a link is alive and is not obviously parked or hijacked. We do not scan for malware, and a site could change after the last check.
• They do not judge quality. A site can be alive and no longer funny.
• They can be wrong. An automated check can miss a quiet takeover or flag a healthy site. If you spot a mistake, use the Report broken link button on any site page, or contact us.

Why we do this

Because the odd web is fragile. Domains lapse, creators move on and old names get bought. A directory that does not check its links is a directory of memories. We would rather tell you honestly that something has gone.

See also: About, Submission guidelines.