check web redirect url status code checker

Check server response of

Server response
NS records
Whois domain
Response headers
Request headers
Raw HTML code
412 Precondition Failed - ctac1.com
HTTP Status: 412
User-Agent: Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; [email protected])
Date: Sun, 11 May 2025 10:55:17 GMT
Server: Apache
Upgrade: h2
Connection: Upgrade
Accept-Ranges: bytes
Content-Length: 1004
Content-Type: text/html

HTTP Code 412 Precondition Failed

412 status code indicates that one or more conditions in the request header fields were not met by the server.

When is Code 412 used?

  • When a request contains an If-Match or If-Unmodified-Since header that fails validation
  • When an API request includes preconditions that the server cannot satisfy
  • When a resource update is attempted with outdated conditions

What does Code 412 mean for the user?

The request is rejected because one or more conditions are not met. The user may need to refresh data or retry with updated request parameters.

GET / HTTP/1.1
Host: ctac1.com
Accept: */*
User-Agent: Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; [email protected])

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
	<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
	<title>412 Request Blocked</title>
	<link href="/icons/expired/style.css" rel="stylesheet" type="text/css" />
</head>

<body>
	<div id="notice">
		<h1>412 REQUEST BLOCKED</h1>
		<h2>Precondition failed: the web server has blocked this request for security reasons.</h2>
	</div>
	<div>
		<p>You may want to contact the webmaster and inform them <br />
		of the time the error occurred, as well as anything you might have <br />
		done that may have caused the error.</p>
		<br>
		<p>If you are the owner of the website, you can get more information about <br />
		the issue and how to resolve it in the article <a href="https://tickets.suresupport.com/faq/article-1596/en">Error "412 Precondition Failed" (mod_security2)</a>.<br /></p>
	</div>
</body>
</html>

Whois info of domain

Domain Name: CTAC1.COM
Registry Domain ID: 122887201_DOMAIN_COM-VRSN
Registrar WHOIS Server: whois.tucows.com
Registrar URL: http://www.tucows.com
Updated Date: 2024-06-20T20:58:15Z
Creation Date: 2004-06-19T08:06:16Z
Registry Expiry Date: 2025-06-19T08:06:16Z
Registrar: Tucows Domains Inc.
Registrar IANA ID: 69
Registrar Abuse Contact Email: [email protected]
Registrar Abuse Contact Phone: +1.4165350123
Domain Status: clientTransferProhibited https://icann.org/epp#clientTransferProhibited
Domain Status: clientUpdateProhibited https://icann.org/epp#clientUpdateProhibited
Name Server: NS1.POWWEB.COM
Name Server: NS2.POWWEB.COM
DNSSEC: unsigned
URL of the ICANN Whois Inaccuracy Complaint Form: https://www.icann.org/wicf/
>>> Last update of whois database: 2025-05-11T10:55:05Z <<<
For more information on Whois status codes, please visit https://icann.org/epp
NOTICE: The expiration date displayed in this record is the date the
TERMS OF USE: You are not authorized to access or query our Whois
by the following terms of use: You agree that you may use this Data only
to: (1) allow, enable, or otherwise support the transmission of mass