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https://itmedia.co.jp

Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
78
GRADE
C
FIX
1
REVIEW
4
PASS
3
INFO
1
Probed from Singapore, Singapore
301 Moved Permanently
Checks
9
3 PASS 4 REVIEW 1 FIX
D
CDN & Delivery
Action
No CDN detected
FIX
No CDN detected
Warning::
No CDN detected
A CDN can significantly improve load times for users around the world by caching content at edge nodes closer to them.
No CDN detected

Consider using a CDN to improve global delivery speed and reduce origin load.

C
IPv6 Readiness
Action
No IPv6 support
REVIEW
No IPv6 support
Info::
No IPv6 (AAAA) records found
IPv6 support is increasingly important for global accessibility. About 40% of internet users have IPv6 connectivity.
No IPv6 Support
About 40% of internet users have IPv6. Consider adding AAAA records.

IPv6 support is increasingly important for global accessibility. About 40% of internet users have IPv6 connectivity.

Why this matters

No AAAA records — same impact as 'no IPv6 (AAAA) records'; IPv6-preferring clients pay extra latency falling back to IPv4.

Source: Google IPv6 stats

C
Crawlability
Action
robots.txt present, sitemap with 0 URLs
REVIEW
robots.txt present, sitemap with 0 URLs
Info::
robots.txt is present
Got: 10240 bytes
Info::
sitemap.xml is present
Warning::
sitemap.xml contains invalid XML
Search engines may not be able to parse the sitemap. Fix XML validation errors.
Warning::
sitemap.xml is empty — no URLs found
An empty sitemap provides no value. Add <url> entries for your pages.
Info::
robots.txt does not reference a sitemap
Add a 'Sitemap:' directive to robots.txt so search engines can discover your sitemap.

Search engines may not be able to parse the sitemap. Fix XML validation errors.

Why this matters

An unparseable sitemap is silently ignored by Google — the URLs it advertises are never queued for crawl.

Learn more ▾

Google's sitemap parser is strict about XML validity. A single unescaped `&` or unclosed tag invalidates the whole file. Run your sitemap through a validator (Search Console's Sitemaps report flags it) and fix the offending entry. Most generators escape correctly; mistakes usually come from manually-written entries.

Source: sitemaps.org / Google Search Central

An empty sitemap provides no value. Add <url> entries for your pages.

Why this matters

An empty sitemap signals 'no content to index' to Google — actively harmful versus having no sitemap at all.

Learn more ▾

Google compares URLs in the sitemap against URLs it has crawled. An empty sitemap on a site with thousands of pages signals abandonment. Either populate it correctly (most CMSes auto-generate) or delete the file and let Google crawl normally.

Source: Google Search Central / sitemaps.org

Add a 'Sitemap:' directive to robots.txt so search engines can discover your sitemap.

Why this matters

robots.txt omits Sitemap: directive — crawlers must fetch /sitemap.xml by convention; reliable but missing the explicit hint.

Source: sitemaps.org

robots.txt 200 OK
Size 10240 B Sitemaps referenced 0 User-agents Blocking No — crawling allowed























<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">

<html lang="ja" id="masterChannel-top"><head>
<meta name="facebook-domain-verification" content="zq54k16jqxhtqyya91r57gtig1xtb4" />
<meta http-equiv="content-type" content="text/html;charset=shift_jis">
<meta http-equiv="content-style-type" content="text/css">
<meta http-equiv="content-script-type" content="text/javascript">

<meta name="referrer" content="no-referrer-when-downgrade">


<meta http-equiv="X-UA-Compatible" content="IE=Edge">

<script>var swspv = '(none)';var cms_summary_flag = '(none)';</script>
<script src="/js/spv/movePC2SP.js?date=250916104008"></script>
<!-- FIX DMOZ -->

	<!-- masterType = top -->
	<meta name="robots" content="noodp">
	<meta name="robots" content="noydir">
	<meta name="msvalidate.01" content="A0217C685F39C036AA269B48F707167C">


	<!-- masterType ne article -->










<meta name="build" content="2026�N04��22�� 09��40��">
<meta name="keywords" content="IT,�j���[�X,�G���^�[�v���C�Y,���o�C��,���C�t�X�^�C��,PC,�Q�[��,blog">
<meta name="description" content="�e�N�m���W�[�֘A�̃j���[�X�y�ё����𒆐S�ɁA���r���[�����W�L�����f�ځB">
<meta name="adpath" content="root/ITmedia/top">
<meta name="verify-v1" content="qWxR2mkYfreZ4abj9sVAHK4PuZxSDd1biwQncTvLhEA=">
<meta name="google-site-verification" content="zQguCQHPB5SxnBZQBeCTqbv5zFWGI1I_EgfnqL-zu2o">
<title>IT���������|�[�^���uITmedia�vHome</title>


<meta name="twitter:card" content="summary">
<meta name="twitter:site" content="@topitmedia">
<meta name="twitter:creator" content="@topitmedia">
<meta property="og:site_name" content="ITmedia">
<meta property="og:title" content="IT���������|�[�^���uITmedia�vHome">
<meta property="og:description" content="�e�N�m���W�[�֘A�̃j���[�X�y�ё����𒆐S�ɁA���r���[�����W�L�����f�ځB">
<meta property="og:url" content="https://www.itmedia.co.jp/">
<meta property="og:type" content="website">
<meta property="og:image" content="https://image.itmedia.co.jp/images/logo/1200x630_500x500_top.gif">
<meta property="fb:app_id" content="127564034422715">
<link rel="canonical" href="https://www.itmedia.co.jp/">
<link rel="alternate" media="only screen and (max-width: 640px)" href="https://www.itmedia.co.jp/spv/">
<meta name="viewport" content="width=device-width">

<link rel="alternate" type="application/rss+xml" title="ITmedia TOP STORIES" href="https://rss.itmedia.co.jp/rss/2.0/topstory.xml">


<link rel="stylesheet" href="https://www.itmedia.co.jp/css/base.css?202509161104" type="text/css" media="all">
<link rel="stylesheet" href="https://www.itmedia.co.jp/css/top/base.css?202511251430" type="text/css" media="all">





<script src="//fc.itmedia.co.jp/fpcookie?site_id=itm_"></script>




<script type="text/javascript" src="/js/base_v2.js?202501291050"></script>

<script src="https://cdn.cxense.com/cx.js"></script>
<script src="/js/lib/cx_v2.js?202507231610"></script>
<script>
var cx_segments = '';
cx_segments = cX.getUserSegmentIds({persistedQueryId:'32780b6d6fb51c7b1fefeb67a7e3305b165e5c6a'});
</script>
<!-- GAM�ݒ� -->
<script async="async" src="https://flux-cdn.com/client/00046/itmedia_01591.min.js"></script>
<script src="/js/gamServerEnvironment.js?date=202107151140"></script>
<script>
window.googletag = window.googletag || {};
window.googletag.cmd = window.googletag.cmd || [];
</script>
<script async src="https://securepubads.g.doubleclick.net/tag/js/gpt.js"></script>
<script>
// ���ʏ���
window.gam_logop = {};
window.gam_media = 'top';
// Key-Value�ݒ�
const gam_keyValue = function(){
	const gam_server = gam_serverenvironment();
	const gam_host = location.protocol + '\/\/' + location.host;
	const gam_url = location.pathname.replace(/\/index.html$/,'\/');
	if(cx_segments.length >= 200) cx_segments = cx_segments.slice(0,200);
	const gam_composite = String((new Date().getTime() % 12)+1);
	googletag.pubads().setTargeting('server',gam_server).setTargeting('host',gam_host).setTargeting('url',gam_url).setTargeting('CxSegments',cx_segments);
	googletag.pubads().setTargeting('itm_adpath_4','top').setTargeting('composite',gam_composite);
}
// �z�M�ݒ�
const gamDeliveryCheck = function(){
	googletag.pubads().addEventListener('slotRenderEnded',function(e){
		const gam_slotid = e.slot.getSlotElementId();
		const gam_slotdiv = document.getElementById(gam_slotid);
// �z�M�󋵃��O
		if(gam_logop) gam_logop[gam_slotid] = e;
// �z�M�A���z�M����
		const gam_delivery = e.isEmpty;
// �T�C�Y����
		const gam_wpsize = /(WallPaper)/.test(gam_slotid);
		const gam_sbsize = /(SuperBanner)/.test(gam_slotid);
// 1�g�ړ��e����
		const gam_firstset = /(_headline$|_1$)/;
		const gam_firstcheck = gam_firstset.test(gam_slotid);
// SB�T�C�Y�w��
		const gam_sb = /(PC_SuperBanner)/.test(gam_slotid);
		if(gam_sb) document.getElementById('PC_SuperBanner').style.minHeight = e.size[1] + 'px';
// �����L���Ή�
		if(gam_wpsize||gam_firstcheck){
			let gam_noadflag = gam_delivery ? 'noad' : 'delivery';
			const gam_adposition = gam_wpsize ? gam_slotdiv.closest('.WallPaperIn') : gam_slotdiv.parentNode;
			const gam_adpch = gam_adposition.children[0];
			const gam_adpchcheck = gam_adpch.classList.contains('adnotation');
			const gam_hlcheck = gam_adpch.classList.contains('gam_headline');
			const gam_hedline = {
				'PC_TopBox-ITS_1': 'IT���i�ESaaS�I�с@from IT�Z���N�g',
				'PC_OwnedAd_1': 'PR-Features',
				'PC_upp-BrandText_1': '<p>Special Contents</p>',
				'PC_low-BrandText_1': '<p>Brand Topics</p>'
			};
			let gam_hltext = gam_hedline[gam_slotdiv.id] || 'Special';
			gam_hltext += '<span class="gam_prmark">PR</span>';
			if(gam_hlcheck && gam_noadflag == 'delivery' && gam_adpch.innerHTML == '') gam_adpch.innerHTML = gam_hltext;
			gam_adposition.classList.add(gam_noadflag);
			if(gam_wpsize && e.size){
				if(e.size != '1,1'){
					if(e.size[0] > 1) gam_adposition.style.width = e.size[0] + 'px';
					if(e.size[1] > 1) gam_adposition.style.height = e.size[1] + 'px';
					if(/(_left$)/.test(gam_slotid)) gam_adposition.style.left = '-' + (e.size[0] + 8) + 'px';
					if(/(_right$)/.test(gam_slotid)) gam_adposition.style.right = '-' + (e.size[0] + 8) + 'px';
					const mb = document.getElementById('masterBody');
					if(mb) mb.classList.add('WpSet');
				} else {
					gam_adposition.style.display = 'none';
				}
			}
			if(gam_hlcheck && gam_noadflag == 'noad') gam_adpch.innerHTML = '';
		}
		if(gam_sbsize && e.size != '1,1'){
			if(e.size[0] < 970) gam_slotdiv.style.minWidth = e.size[0] + 'px';
			if(e.size[1] < 250) gam_slotdiv.style.minHeight = e.size[1] + 'px';
		}
	});
};
// refresh
const refreshGam = function(slot,dc){
	googletag.cmd.push(function(){
		let gframe = '';
		if(slot == 'WallPaper') gframe = [gam_wpl,gam_wpr,gam_spb];
		if(slot == 'TopicsarchiveAd') gframe = [gam_ifn11,gam_ifn12,gam_tx1,gam_tx2,gam_tx3];
		if(slot == 'TopicsarchiveBtmAd') gframe = [gam_ifn2,gam_tb1,gam_tb2,gam_tb3,gam_tb4,gam_tbi1,gam_tbi2,gam_om1,gam_om2,gam_om3];
		if(slot == 'BrandText') gframe = [gam_ubt1,gam_ubt2,gam_ubt3,gam_ubt4,gam_ubt5,gam_lbt1,gam_lbt2,gam_lbt3,gam_lbt4,gam_lbt5,gam_lbt6,gam_lbt7,gam_lbt8,gam_lbt9,gam_lbt10];
		if(slot == 'SideLink') gframe = [gam_sl1,gam_sl2,gam_sl3,gam_sl4,gam_sl5,gam_sl6,gam_sl7,gam_sl8,gam_sl9,gam_sl10,gam_sl11,gam_sl12,gam_sl13,gam_sl14,gam_sl15,gam_sl16,gam_sl17,gam_sl18,gam_sl19,gam_sl20];
		if(slot == 'RcolRectangle2') gframe = [gam_rct1,gam_rct2];
		if(gframe) googletag.pubads().refresh(gframe);
		if(dc) gamDeliveryCheck();
	});
};
// refresh����
// ����
var gam_wpl,gam_wpr,gam_spb,gam_ifn11,gam_ifn12,gam_tx1,gam_tx2,gam_tx3,gam_ifn2,gam_tb1,gam_tb2,gam_tb3,gam_tb4,gam_om1,gam_om2,gam_om3,gam_ubt1,gam_ubt2,gam_ubt3,gam_ubt4,gam_ubt5,gam_lbt1,gam_lbt2,gam_lbt3,gam_lbt4,gam_lbt5,gam_lbt6,gam_lbt7,gam_lbt8,gam_lbt9,gam_lbt10,gam_rct1,gam_rct2,gam_sl1,gam_sl2,gam_sl3,gam_sl4,gam_sl5,gam_sl6,gam_sl7,gam_sl8,gam_sl9,gam_sl10,gam_sl11,gam_sl12,gam_sl13,gam_sl14,gam_sl15,gam_sl16,gam_sl17,gam_sl18,gam_sl19,gam_sl20,gam_tbi1,gam_tbi2;
googletag.cmd.push(function(){
	googletag.pubads().collapseEmptyDivs();
	const sd = '/43042345/top/';
	gam_wpl = googletag.defineSlot(sd + 'PC_WallPaper-left',[[160,600],[160,1024],[1,1]],'PC_WallPaper_left').addService(googletag.pubads());
	gam_wpr = googletag.defineSlot(sd + 'PC_WallPaper-right',[[160,600],[160,1024],[1,1]],'PC_WallPaper_right').addService(googletag.pubads());
	gam_spb = googletag.defineSlot(sd + 'PC_SuperBanner',[[728,90],[970,90],[728,180],[970,250],[970,400],[1,1]],'PC_SuperBanner').addService(googletag.pubads());
	gam_ifn11 = googletag.defineSlot(sd + 'PC_upp-in-feed-Native',[[670,114]],'PC_upp-in-feed-Native_1').setTargeting('slot_pos','1').addService(googletag.pubads());
	gam_ifn12 = googletag.defineSlot(sd + 'PC_upp-in-feed-Native',[[670,114]],'PC_upp-in-feed-Native_2').setTargeting('slot_pos','2').addService(googletag.pubads());
	gam_tx1 = googletag.defineSlot(sd + 'PC_lcol-Text',[[670,32]],'PC_lcol-Text_1').setTargeting('slot_pos','1').addService(googletag.pubads());
	gam_tx2 = googletag.defineSlot(sd + 'PC_lcol-Text',[[670,32]],'PC_lcol-Text_2').setTargeting('slot_pos','2').addService(googletag.pubads());
	gam_tx3 = googletag.defineSlot(sd + 'PC_lcol-Text',[[670,32]],'PC_lcol-Text_3').setTargeting('slot_pos','3').addService(googletag.pubads());
	gam_ifn2 = googletag.defineSlot(sd + 'PC_low-in-feed-Native',[[670,114]],'PC_low-in-feed-Native').addService(googletag.pubads());
	gam_tb1 = googletag.defineSlot(sd + 'PC_TopBox',[[670,106]],'PC_TopBox_1').setTargeting('slot_pos','1').setTargeting('media',[gam_media]).addService(googletag.pubads());
	gam_tb2 = googletag.defineSlot(sd + 'PC_TopBox',[[670,106]],'PC_TopBox_2').setTargeting('slot_pos','2').setTargeting('media',[gam_media]).addService(googletag.pubads());
	gam_tb3 = googletag.defineSlot(sd + 'PC_TopBox',[[670,106]],'PC_TopBox_3').setTargeting('slot_pos','3').setTargeting('media',[gam_media]).addService(googletag.pubads());
	gam_tb4 = googletag.defineSlot(sd + 'PC_TopBox',[[670,106]],'PC_TopBox_4').setTargeting('slot_pos','4').setTargeting('media',[gam_media]).addService(googletag.pubads());
	gam_om1 = googletag.defineSlot(sd + 'PC_OwnedAd',[[670,106]],'PC_OwnedAd_1').setTargeting('slot_pos','1').addService(googlet
sitemap.xml 200 OK
Type URL Set URLs 0 entries Valid XML No
B
URL Variants
www/non-www, trailing slash, HTTP→HTTPS
REVIEW
www/non-www, trailing slash, HTTP→HTTPS
Critical::
Both www and non-www versions serve content
Got: Both variants return 200 Expected: One variant 301-redirects to the other
Info::
HTTP correctly 301-redirects to HTTPS

www / non-www

200https://www.itmedia.co.jp/
200https://itmedia.co.jp/

Inconsistent — duplicate content risk

HTTP → HTTPS

301http://itmedia.co.jp/ → https://itmedia.co.jp/

Consistent

B
TLS Certificate Expiry & Recommendations
246 days until leaf cert expires — 5 issues to address
REVIEW

Certificate validity

246
days left
0d 30d 60d 90d+

Recommended actions

  • Prefer TLS 1.3 — TLS 1.2 is acceptable but TLS 1.3 removes RSA key exchange and improves latency
  • Add includeSubDomains to the HSTS directive
  • Add the preload directive and submit to hstspreload.org once max-age + includeSubDomains are in place
  • Enable DNSSEC on your domain for DNS spoofing protection
  • Enable OCSP stapling on your TLS server to remove a CA roundtrip and protect user privacy
A+
DNS Records
2 A records, 7 ms lookup
PASS
2 A records, 7 ms lookup
Info::
Resolves to 2 IPv4 address(es)
Got: 54.64.44.182, 52.193.230.47
Info::
No IPv6 (AAAA) records
Info::
4 nameserver(s) configured
Got: ns-1227.awsdns-25.org, ns-1806.awsdns-33.co.uk, ns-909.awsdns-49.net, ns-99.awsdns-12.com
Info::
1 mail exchanger(s) configured
Info::
CAA records not checked
CAA record lookup requires a specialized DNS resolver. This check will be available in a future update.
Info::
SPF record present in TXT
Info::
DNS resolution time: 7 ms
Got: 7 ms
A54.64.44.182, 52.193.230.47
AAAA—
CNAME—
NSns-1227.awsdns-25.org, ns-1806.awsdns-33.co.uk, ns-909.awsdns-49.net, ns-99.awsdns-12.com
MX
10 anymx02.itmedia.co.jp
TXT
d8cc92269c2a4be0e690a96c007683ec.itmedia.co.jp
pardot427772=514b422fa508c922765af22d0adcf3c560a058fd2d1a6889ee1053baac8a24c6
pardot_291242_*=9f9ade131ab0deaadeb93b0e0256e74ac2c0f00e3142e8579c012715c5054dc1
SPF v=spf1 a:spf.itmedia.co.jp a:spf-magfire.itmedia.co.jp +ip4:113.35.66.0/24 a:spf...
CAALookup not available with standard resolver
Resolved in 7 ms

CAA record lookup requires a specialized DNS resolver. This check will be available in a future update.

Why this matters

Informational: CAA (Certification Authority Authorization) records weren't checked in this scan.

A
Redirect Chain
1 redirect(s), 647 ms total
PASS
1 redirect(s), 647 ms total
Info::
Single redirect
Got: https://itmedia.co.jp → https://www.itmedia.co.jp/ (301)
Info::
WWW normalization redirect
Info::
Redirect overhead: 647 ms total
Got: 647 ms

https://itmedia.co.jp

288 ms · HTTP/1.1

301

https://www.itmedia.co.jp/

359 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://itmedia.co.jp301288 msHTTP/1.1nginx
2https://www.itmedia.co.jp/200359 msHTTP/1.1nginx

See the visual redirect chain in the HTTP Probe tab →

A+
HTTP Probe Timing
Total 374 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
PASS
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
102 ms
TCP Connect TCP Connect — time to establish a TCP connection to the server.
67 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
137 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
374 ms
Total Time Total request time from DNS lookup through full response.
374 ms

Connection waterfall

DNS Lookup 102 ms TCP Connect 67 ms TLS Handshake 137 ms Server Processing 68 ms Content Transfer 0 ms
Domain Intelligence
Domain intelligence data not available
INFO
Domain intelligence data not available

RDAP and WHOIS lookup both failed

All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.

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