atcoder.jp - dns.ninja

`atcoder.jp`

DNSSEC	⚠️ Not signed
A	54.230.201.3^{🇺🇸 Amazon54.224.0.0/12 NA prefix}
		PTR	`server-54-230-201-3.lhr82.r.cloudfront.net`
A	54.230.201.27^{🇺🇸 Amazon54.224.0.0/12 NA prefix}
A	54.230.201.64^{🇺🇸 Amazon54.224.0.0/12 NA prefix}
A	54.230.201.118^{🇺🇸 Amazon54.224.0.0/12 NA prefix}
NS	`ns-96.awsdns-12.com` ⭐
		A	2600:9000:5300:6000::1^{🇺🇸 Amazon2600:9000:5300::/48 - CloudFront}
			PTR	`ns-96.awsdns-12.com`
		A	205.251.192.96^{🇺🇸 Amazon205.251.192.0/24 prefix}
			PTR	`ns-96.awsdns-12.com`
NS	`ns-1144.awsdns-15.org`
		A	2600:9000:5304:7800::1^{🇺🇸 Amazon2600:9000:5304::/48 - CloudFront}
			PTR	`ns-1144.awsdns-15.org`
		A	205.251.196.120^{🇺🇸 Amazon205.251.196.0/24 prefix}
			PTR	`ns-1144.awsdns-15.org`
NS	`ns-1543.awsdns-00.co.uk`
		A	2600:9000:5306:700::1^{🇺🇸 Amazon2600:9000:5306::/48 - CloudFront}
			PTR	`ns-1543.awsdns-00.co.uk`
		A	205.251.198.7^{🇺🇸 Amazon205.251.198.0/24 prefix}
			PTR	`ns-1543.awsdns-00.co.uk`
NS	`ns-890.awsdns-47.net`
		A	2600:9000:5303:7a00::1^{🇺🇸 Amazon2600:9000:5303::/48 - CloudFront}
			PTR	`ns-890.awsdns-47.net`
		A	205.251.195.122^{🇺🇸 Amazon205.251.195.0/24 prefix}
			PTR	`ns-890.awsdns-47.net`
MX	`aspmx.l.google.com` ⭐
		A	2a00:1450:4009:c0f::1a^{🇬🇧 Google2a00:1450:4009::/48}
			PTR	`yulhrs-in-f26.1e100.net`
		A	192.178.223.27^{🇺🇸 Google192.178.223.0/24}
			PTR	`yulhrs-in-f27.1e100.net`
MX	`alt1.aspmx.l.google.com`⁽²⁰⁾
		A	2a00:1450:4025:402::1b^{🇳🇱 Google2a00:1450:4025::/48}
			PTR	`rb-in-f27.1e100.net`
		A	142.250.102.27^{🇺🇸 Google142.250.102.0/24}
			PTR	`rb-in-f27.1e100.net`
MX	`alt2.aspmx.l.google.com`⁽²⁰⁾
		A	2a00:1450:4013:c1e::1a^{🇳🇱 Google2a00:1450:4013::/48}
			PTR	`yugrqzs-in-f26.1e100.net`
		A	192.178.213.27^{🇺🇸 Google192.178.213.0/24}
			PTR	`yugrqzs-in-f27.1e100.net`
MX	`aspmx2.googlemail.com`⁽³⁰⁾
		A	2a00:1450:4025:402::1a^{🇳🇱 Google2a00:1450:4025::/48}
			PTR	`rb-in-f26.1e100.net`
		A	142.250.102.27^{🇺🇸 Google142.250.102.0/24}
			PTR	`rb-in-f27.1e100.net`
MX	`aspmx3.googlemail.com`⁽³⁰⁾
		A	2a00:1450:4013:c1e::1b^{🇳🇱 Google2a00:1450:4013::/48}
			PTR	`yugrqzs-in-f27.1e100.net`
		A	192.178.213.26^{🇺🇸 Google192.178.213.0/24}
			PTR	`yugrqzs-in-f26.1e100.net`
MX	`aspmx4.googlemail.com`⁽³⁰⁾
		A	2a00:1450:4025:c01::1a^{🇵🇱 Google2a00:1450:4025::/48}
			PTR	`rd-in-f26.1e100.net`
		A	142.251.127.27^{🇺🇸 Google142.251.127.0/24}
			PTR	`lcfrai-in-f27.1e100.net`
MX	`aspmx5.googlemail.com`⁽³⁰⁾
		A	2a00:1450:4025:c01::1b^{🇵🇱 Google2a00:1450:4025::/48}
			PTR	`rd-in-f27.1e100.net`
		A	172.253.152.26^{🇺🇸 Google172.253.0.0/16}
			PTR	`yulpptr-in-f26.1e100.net`
TXT	`1password-site-verification=H3CJM364F5GI5P3VXH2PYFGCKI`
TXT	`MS=ms90685883`
TXT	`cloudflare_dashboard_sso=f62aac0af9122a7fff211950f317b6df`
TXT	`google-site-verification=IIyyB5yMWakA7SnvZLuqk-eBDlEj647aY0Rq-c80uIg`
TXT	`google-site-verification=iiXXCv8YJjdE0FWPz6zq0ispBt688ytJaOQfOpwuU3A`
TXT	`pardot884953=58ccd91e72a6f94be7450fef89ee32f712f9e18afb5273954e7d09781c220ec1`
TXT	`stripe-verification=e726551d53f6bea6b1a960e876e9fd88c34f32b723a3b2ecb1a91dfc3...`
TXT	`v=spf1 a:atcoder.jp include:_spf.google.com include:aspmx.pardot.com include:...`
SOA	`ns-96.awsdns-12.com`awsdns-hostmaster@amazon.com serial=1

`jp`

	DNSSEC	🔒 Signed (DS record present)
	NS	`z.dns.jp` ⭐
	NS	`a.dns.jp`
	NS	`b.dns.jp`
	NS	`c.dns.jp`
	NS	`d.dns.jp`
	NS	`e.dns.jp`
	NS	`f.dns.jp`
	NS	`g.dns.jp`
	NS	`h.dns.jp`
	SOA	`z.dns.jp`root@dns.jp serial=1781808303

rank #49594 globally
rank #1016 in the tld
📈 Tranco rank: #40,594

Subdomains

info.atcoder.jp

img.atcoder.jp

past.atcoder.jp

Same first word

atcoder.co.jp

atcoder.org

atcoder.jp

atcoder.biz

atcoder.info

Similar names

teradoc.fr

artdeco.store

dotcaer.com

redcoat.ai

decoart.at

codeart.co.uk

dotcrea.net

roadtec.com.uy

artdeco.se

codetra.com

codeart.pl

rodatec.com

artedoc.nl

artdeco.hk

artcode.in

artcode.com.au

teraodc.com

artdeco.ch

daocert.com

artdeco.info

decorat.co

artdeco.cz

artdeco.de

artdeco.ca

artedco.com

cartedo.com

codeart.us

decoart.es

octaedr.info

docrate.com

tradeco.online

tradeco.pro

artcode.ltd

redcoat.de

decoart.fi

cadoret.com

coredat.at

cordate.tw

artcode.co.uk

artcode.by

cortade.net

codeart.co.il

caterdo.com

credota.live

redcoat.biz

tradeco.ca

coredat.net

doreact.com

cotrade.cn

artcode.co.jp

cotarde.com

redcoat.eu

artdeco.at

cardeto.it

artdeco.org.au

artcode.com

tradeco.cz

roadtec.com

doratec.ch

decoart.co.uk

roadtec.com.ua

teradoc.com

cotrade.co

redacto.org

ardotec.com

coredat.com

doctera.com

decorat.ru

codeart.vn

tedraco.com

ecotrad.org

decarto.com

deactro.nl

decorat.com

doecart.com

decoart.fr

decoart.to

tradeco.com.vn

tarcode.ru

decoart.online

decorat.com.mx

cadoret.fr

treadco.com

codeart.com.au

decotra.com

cadoret.myshopify.com

artcode.com.ua

tadecor.vn

roadtec.net

cotrade.de

cardeto.org

artdeco.nl

artecod.net

dertaco.net

artcode.eu

cotrade.it

ecotrad.it

artdeco.diamonds

cadoret.ca

DNS History

69 records (15 active, 54 former)

●NSns-1144.awsdns-15.org2017-05-24 → 2026-06-18 · 3 obs

○ 2016-07-16 04:50:00
● 2017-05-24 06:16:14
● 2026-06-18 19:45:04

●NSns-1543.awsdns-00.co.uk2017-05-24 → 2026-06-18 · 3 obs

○ 2016-07-16 04:50:00
● 2017-05-24 06:16:14
● 2026-06-18 19:45:04

●NSns-890.awsdns-47.net2017-05-24 → 2026-06-18 · 3 obs

○ 2016-07-16 04:50:00
● 2017-05-24 06:16:14
● 2026-06-18 19:45:04

●NSns-96.awsdns-12.com2017-05-24 → 2026-06-18 · 3 obs

○ 2016-07-16 04:50:00
● 2017-05-24 06:16:14
● 2026-06-18 19:45:04

○NSns1.value-domain.com2015-08-13 → 2016-07-16 · 4 obs

● 2015-08-13 18:44:32
● 2016-07-16 04:50:00
○ 2017-05-24 06:16:14
○ 2026-06-18 19:45:04

○NSns2.value-domain.com2015-08-13 → 2016-07-16 · 4 obs

● 2015-08-13 18:44:32
● 2016-07-16 04:50:00
○ 2017-05-24 06:16:14
○ 2026-06-18 19:45:04

●MXalt1.aspmx.l.google.com2015-08-13 → 2026-06-18 · 2 obs

● 2015-08-13 18:44:32
● 2026-06-18 19:45:04

●MXalt2.aspmx.l.google.com2015-08-13 → 2026-06-18 · 2 obs

● 2015-08-13 18:44:32
● 2026-06-18 19:45:04

●MXaspmx.l.google.com2015-08-13 → 2026-06-18 · 2 obs

● 2015-08-13 18:44:32
● 2026-06-18 19:45:04

●MXaspmx2.googlemail.com2015-08-13 → 2026-06-18 · 2 obs

● 2015-08-13 18:44:32
● 2026-06-18 19:45:04

●MXaspmx3.googlemail.com2015-08-13 → 2026-06-18 · 2 obs

● 2015-08-13 18:44:32
● 2026-06-18 19:45:04

●MXaspmx4.googlemail.com2015-08-13 → 2026-06-18 · 2 obs

● 2015-08-13 18:44:32
● 2026-06-18 19:45:04

●MXaspmx5.googlemail.com2015-08-13 → 2026-06-18 · 2 obs

● 2015-08-13 18:44:32
● 2026-06-18 19:45:04

○A108.156.85.1092026-03-31 → 2026-06-16 · 87 obs

○ 2026-03-29 22:43:20
● 2026-03-31 10:52:36
○ 2026-04-02 06:31:10
○ 2026-04-09 07:48:54
● 2026-04-10 09:03:20
○ 2026-04-10 13:38:10
● 2026-04-10 14:45:46
○ 2026-04-10 23:38:46
○ 2026-04-12 06:38:00
● 2026-04-12 11:36:40
○ 2026-04-13 01:37:50
● 2026-04-13 07:09:50
○ 2026-04-13 08:05:26
○ 2026-04-14 07:02:46
● 2026-04-14 07:51:18
● 2026-04-15 13:20:46
○ 2026-04-15 18:24:28
● 2026-04-17 01:42:46
○ 2026-04-17 15:43:44
○ 2026-04-24 21:22:18
● 2026-04-25 01:03:40
○ 2026-04-25 02:21:32
○ 2026-04-25 08:02:42
● 2026-04-25 11:53:46
○ 2026-04-25 17:53:16
○ 2026-04-27 13:39:04
● 2026-04-27 17:44:52
○ 2026-04-27 18:40:04
○ 2026-04-29 03:58:12
● 2026-04-29 11:44:44
○ 2026-04-29 12:55:46
○ 2026-04-30 14:32:52
● 2026-04-30 15:18:08
○ 2026-04-30 17:08:32
● 2026-04-30 19:36:52
○ 2026-04-30 21:49:12
○ 2026-05-06 05:45:06
● 2026-05-06 11:00:46
● 2026-05-06 14:45:50
○ 2026-05-06 15:42:02
○ 2026-05-07 23:35:20
● 2026-05-08 02:23:56
○ 2026-05-08 04:30:06
○ 2026-05-10 00:51:34
● 2026-05-10 05:41:04
○ 2026-05-10 11:07:38
○ 2026-05-13 02:11:56
● 2026-05-13 10:04:50
○ 2026-05-13 10:42:56
● 2026-05-13 17:24:16
○ 2026-05-13 22:13:06
● 2026-05-14 15:42:52
○ 2026-05-14 23:12:54
○ 2026-05-22 01:00:00
● 2026-05-22 04:54:20
○ 2026-05-22 06:19:42
○ 2026-05-27 01:56:22
● 2026-05-27 05:33:04
○ 2026-05-27 12:47:04
● 2026-05-27 20:33:20
● 2026-05-28 01:04:32
○ 2026-05-28 03:36:34
○ 2026-05-29 07:55:18
● 2026-05-29 16:18:42
○ 2026-05-30 06:31:00
○ 2026-05-30 20:10:00
● 2026-05-31 12:46:18
● 2026-06-01 11:56:02
○ 2026-06-01 22:19:22
○ 2026-06-02 11:50:46
● 2026-06-02 15:28:14
○ 2026-06-02 19:57:30
○ 2026-06-04 03:46:54
● 2026-06-04 12:48:04
○ 2026-06-04 17:59:16
● 2026-06-04 18:33:54
○ 2026-06-05 01:13:08
○ 2026-06-07 11:28:28
● 2026-06-07 16:11:30
○ 2026-06-07 20:07:30
○ 2026-06-10 02:18:00
● 2026-06-10 03:16:54
○ 2026-06-11 08:21:52
○ 2026-06-15 23:39:48
● 2026-06-16 03:53:44
○ 2026-06-16 04:34:04
○ 2026-06-18 19:45:04

○A108.156.85.1112026-03-31 → 2026-06-16 · 87 obs

○A108.156.85.462026-03-31 → 2026-06-16 · 87 obs

○A108.156.85.892026-03-31 → 2026-06-16 · 87 obs

○A13.113.48.1902018-06-16 → 2018-09-08 · 5 obs

○ 2017-05-24 06:16:14
● 2018-06-16 00:59:16
● 2018-09-08 01:26:56
○ 2026-02-14 20:08:58
○ 2026-06-18 19:45:04

○A13.226.209.1132026-02-14 → 2026-06-17 · 60 obs

○ 2018-09-08 01:26:56
● 2026-02-14 20:08:58
● 2026-02-19 04:49:56
○ 2026-02-19 07:44:18
○ 2026-02-19 12:36:58
● 2026-02-19 13:08:28
● 2026-02-24 02:07:36
○ 2026-02-24 08:58:44
● 2026-02-25 04:31:32
● 2026-03-01 05:17:48
○ 2026-03-01 07:17:12
○ 2026-03-01 14:41:46
● 2026-03-03 00:36:20
● 2026-03-04 01:19:50
○ 2026-03-04 04:08:04
○ 2026-03-12 05:55:12
● 2026-03-12 06:42:52
○ 2026-03-12 10:09:52
○ 2026-03-18 05:21:00
● 2026-03-18 11:17:50
○ 2026-03-18 13:29:54
○ 2026-03-20 08:14:06
● 2026-03-20 10:44:06
○ 2026-03-20 11:16:46
● 2026-03-21 15:01:56
○ 2026-03-21 21:29:32
○ 2026-04-13 07:09:50
● 2026-04-13 08:05:26
○ 2026-04-14 07:02:46
○ 2026-05-24 20:24:08
● 2026-05-25 02:49:38
○ 2026-05-25 06:14:44
○ 2026-05-26 06:23:08
● 2026-05-26 08:12:54
○ 2026-05-26 09:55:06
○ 2026-06-10 03:16:54
● 2026-06-11 08:21:52
● 2026-06-11 09:59:32
○ 2026-06-12 06:09:48
○ 2026-06-12 15:59:16
● 2026-06-12 17:16:58
○ 2026-06-13 00:29:48
○ 2026-06-13 11:08:06
● 2026-06-14 15:00:02
● 2026-06-14 18:38:16
○ 2026-06-14 20:44:50
● 2026-06-15 06:39:22
○ 2026-06-15 09:30:58
● 2026-06-15 10:33:22
● 2026-06-15 13:36:48
○ 2026-06-15 17:02:18
○ 2026-06-15 17:43:46
● 2026-06-15 21:25:34
○ 2026-06-15 23:39:48
○ 2026-06-17 07:48:54
● 2026-06-17 14:01:38
○ 2026-06-17 18:25:52
● 2026-06-17 22:09:18
○ 2026-06-17 23:29:58
○ 2026-06-18 19:45:04

○A13.226.209.192026-02-14 → 2026-06-17 · 60 obs

○A13.226.209.242026-02-14 → 2026-06-17 · 60 obs

○A13.226.209.572026-02-14 → 2026-06-17 · 60 obs

○A13.33.235.1142026-03-25 → 2026-03-25 · 4 obs

○ 2026-03-24 13:03:54
● 2026-03-25 11:25:00
○ 2026-03-25 13:48:44
○ 2026-06-18 19:45:04

○A13.33.235.1272026-03-25 → 2026-03-25 · 4 obs

○ 2026-03-24 13:03:54
● 2026-03-25 11:25:00
○ 2026-03-25 13:48:44
○ 2026-06-18 19:45:04

○A13.33.235.352026-03-25 → 2026-03-25 · 4 obs

○ 2026-03-24 13:03:54
● 2026-03-25 11:25:00
○ 2026-03-25 13:48:44
○ 2026-06-18 19:45:04

○A13.33.235.682026-03-25 → 2026-03-25 · 4 obs

○ 2026-03-24 13:03:54
● 2026-03-25 11:25:00
○ 2026-03-25 13:48:44
○ 2026-06-18 19:45:04

○A18.161.21.1162026-04-24 → 2026-05-26 · 36 obs

○ 2026-04-23 17:23:40
● 2026-04-24 12:34:40
○ 2026-04-24 17:23:42
○ 2026-04-26 11:53:48
● 2026-04-26 15:25:46
○ 2026-04-26 16:55:58
● 2026-04-26 18:02:06
○ 2026-04-26 22:49:40
○ 2026-04-27 03:57:48
● 2026-04-27 08:58:26
● 2026-04-27 13:39:04
○ 2026-04-27 17:44:52
○ 2026-04-30 22:57:22
● 2026-04-30 23:35:48
○ 2026-05-01 00:12:00
○ 2026-05-03 06:06:30
● 2026-05-03 09:12:14
○ 2026-05-03 11:11:10
○ 2026-05-09 06:18:44
● 2026-05-09 19:27:42
● 2026-05-09 22:20:50
○ 2026-05-10 00:51:34
○ 2026-05-10 05:41:04
● 2026-05-10 11:07:38
○ 2026-05-10 14:39:54
○ 2026-05-10 20:28:16
● 2026-05-11 07:05:26
○ 2026-05-11 07:36:32
○ 2026-05-19 12:38:08
● 2026-05-19 16:22:16
● 2026-05-19 18:04:40
○ 2026-05-19 19:43:34
○ 2026-05-26 08:12:54
● 2026-05-26 09:55:06
○ 2026-05-26 13:32:06
○ 2026-06-18 19:45:04

○A18.161.21.432026-04-24 → 2026-05-26 · 36 obs

○A18.161.21.712026-04-24 → 2026-05-26 · 36 obs

○A18.161.21.772026-04-24 → 2026-05-26 · 36 obs

○A18.165.9.1172026-04-06 → 2026-04-06 · 4 obs

○ 2026-04-05 20:25:44
● 2026-04-06 08:50:04
○ 2026-04-06 10:45:08
○ 2026-06-18 19:45:04

○A18.165.9.352026-04-06 → 2026-04-06 · 4 obs

○ 2026-04-05 20:25:44
● 2026-04-06 08:50:04
○ 2026-04-06 10:45:08
○ 2026-06-18 19:45:04

○A18.165.9.82026-04-06 → 2026-04-06 · 4 obs

○ 2026-04-05 20:25:44
● 2026-04-06 08:50:04
○ 2026-04-06 10:45:08
○ 2026-06-18 19:45:04

○A18.165.9.872026-04-06 → 2026-04-06 · 4 obs

○ 2026-04-05 20:25:44
● 2026-04-06 08:50:04
○ 2026-04-06 10:45:08
○ 2026-06-18 19:45:04

○A18.244.202.402026-04-03 → 2026-06-18 · 35 obs

○ 2026-04-02 06:31:10
● 2026-04-03 04:54:28
○ 2026-04-03 17:40:14
○ 2026-04-03 18:30:02
● 2026-04-04 02:17:08
○ 2026-04-04 06:29:14
○ 2026-04-04 07:03:24
● 2026-04-05 00:55:36
○ 2026-04-05 07:17:12
○ 2026-04-07 02:21:42
● 2026-04-08 03:24:30
○ 2026-04-08 15:43:32
● 2026-04-09 04:20:28
○ 2026-04-09 07:48:54
○ 2026-04-11 03:56:16
● 2026-04-11 11:19:48
○ 2026-04-12 06:38:00
○ 2026-04-18 11:51:02
● 2026-04-18 22:59:02
○ 2026-04-19 19:41:18
○ 2026-05-03 14:26:28
● 2026-05-03 15:49:34
○ 2026-05-04 01:24:46
○ 2026-05-06 14:45:50
● 2026-05-06 15:42:02
○ 2026-05-06 16:21:14
○ 2026-05-25 02:49:38
● 2026-05-25 06:14:44
○ 2026-05-25 06:58:10
● 2026-05-25 08:42:56
○ 2026-05-25 12:05:16
○ 2026-06-17 23:29:58
● 2026-06-18 01:53:18
○ 2026-06-18 05:25:50
○ 2026-06-18 19:45:04

○A18.244.202.512026-04-03 → 2026-06-18 · 35 obs

○A18.244.202.752026-04-03 → 2026-06-18 · 35 obs

○A18.244.202.792026-04-03 → 2026-06-18 · 35 obs

○A18.67.233.1012026-06-03 → 2026-06-03 · 7 obs

○ 2026-06-02 19:57:30
● 2026-06-03 04:31:02
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○A18.67.233.1092026-06-03 → 2026-06-03 · 7 obs

○ 2026-06-02 19:57:30
● 2026-06-03 04:31:02
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○A18.67.233.272026-06-03 → 2026-06-03 · 7 obs

○ 2026-06-02 19:57:30
● 2026-06-03 04:31:02
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○A18.67.233.862026-06-03 → 2026-06-03 · 7 obs

○ 2026-06-02 19:57:30
● 2026-06-03 04:31:02
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● 2026-06-03 22:43:52
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○A3.162.112.162026-04-19 → 2026-04-19 · 4 obs

○ 2026-04-18 22:59:02
● 2026-04-19 19:41:18
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○A3.162.112.262026-04-19 → 2026-04-19 · 4 obs

○ 2026-04-18 22:59:02
● 2026-04-19 19:41:18
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○A3.162.112.682026-04-19 → 2026-04-19 · 4 obs

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● 2026-04-19 19:41:18
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○A3.162.112.742026-04-19 → 2026-04-19 · 4 obs

○ 2026-04-18 22:59:02
● 2026-04-19 19:41:18
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○A3.169.231.1122026-02-24 → 2026-03-28 · 40 obs

○ 2026-02-24 02:07:36
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○ 2026-06-18 19:45:04

○A3.169.231.452026-02-24 → 2026-03-28 · 40 obs

○A3.169.231.482026-02-24 → 2026-03-28 · 40 obs

○A3.169.231.552026-02-24 → 2026-03-28 · 40 obs

○A3.170.185.102026-05-19 → 2026-06-08 · 54 obs

○ 2026-05-18 22:26:06
● 2026-05-19 09:14:32
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○A3.170.185.872026-05-19 → 2026-06-08 · 54 obs

○A3.170.185.882026-05-19 → 2026-06-08 · 54 obs

○A3.170.185.972026-05-19 → 2026-06-08 · 54 obs

○A52.69.167.992017-05-24 → 2017-05-24 · 4 obs

○ 2016-07-16 04:50:00
● 2017-05-24 06:16:14
○ 2018-06-16 00:59:16
○ 2026-06-18 19:45:04

○A52.85.31.282026-03-08 → 2026-05-20 · 19 obs

○ 2026-03-06 18:07:04
● 2026-03-08 00:13:48
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● 2026-03-08 17:23:56
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○ 2026-06-18 19:45:04

○A52.85.31.412026-03-08 → 2026-05-20 · 19 obs

○A52.85.31.492026-03-08 → 2026-05-20 · 19 obs

○A52.85.31.582026-03-08 → 2026-05-20 · 19 obs

●A54.230.201.1182026-04-23 → 2026-06-18 · 94 obs

○ 2026-04-22 15:43:14
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● 2026-06-18 05:25:50
● 2026-06-18 19:45:04

●A54.230.201.272026-04-23 → 2026-06-18 · 94 obs

●A54.230.201.32026-04-23 → 2026-06-18 · 94 obs

●A54.230.201.642026-04-23 → 2026-06-18 · 94 obs

○A54.64.33.2152018-06-16 → 2018-09-08 · 5 obs

○ 2017-05-24 06:16:14
● 2018-06-16 00:59:16
● 2018-09-08 01:26:56
○ 2026-02-14 20:08:58
○ 2026-06-18 19:45:04

○A54.64.36.2352015-08-13 → 2016-07-16 · 4 obs

● 2015-08-13 18:44:32
● 2016-07-16 04:50:00
○ 2017-05-24 06:16:14
○ 2026-06-18 19:45:04

○A99.86.91.302026-02-19 → 2026-04-22 · 78 obs

○ 2026-02-19 04:49:56
● 2026-02-19 07:44:18
● 2026-02-19 12:36:58
○ 2026-02-19 13:08:28
○ 2026-03-04 04:08:04
● 2026-03-04 07:49:36
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● 2026-04-22 00:48:16
● 2026-04-22 15:43:14
○ 2026-04-23 11:39:44
○ 2026-06-18 19:45:04

○A99.86.91.512026-02-19 → 2026-04-22 · 78 obs

○A99.86.91.92026-02-19 → 2026-04-22 · 78 obs

○A99.86.91.982026-02-19 → 2026-04-22 · 78 obs

🔍 DNS Trace

📋 Delegation Chain

Zone	Nameservers	Glue
jp	a.dns.jp, b.dns.jp, c.dns.jp, d.dns.jp...	-
atcoder.jp	ns-96.awsdns-12.com, ns-890.awsdns-47.net, ns-1144.awsdns-15.org, ns-1543.awsdns-00.co.uk	-

✅ Authoritative Response

Server:205.251.195.122

NS records: ns-96.awsdns-12.com, ns-890.awsdns-47.net, ns-1144.awsdns-15.org, ns-1543.awsdns-00.co.uk

🔒 DNSSEC Status

⚠️ Insecure (no DNSSEC)

No DS record for atcoder.jp (unsigned zone)

⏱️ Timing

Total: 1635ms | Queries: -

📄 Records

Type	Count	Sample Data
A	4	`13.226.209.57, 13.226.209.113...`
NS	4	`ns-1144.awsdns-15.org, ns-1543.awsdns-00.co.uk...`
MX	7	`aspmx.l.google.com (pri: 10), alt1.aspmx.l.google.com (pri: 20)...`
TXT	8	`1password-site-verification=H3CJM364F5GI, MS=ms90685883...`
SOA	1	`ns-96.awsdns-12.com awsdns-hostmaster.am`

Analysis

Hierarchy

atcoder.jp sits above info.atcoder.jp, img.atcoder.jp and past.atcoder.jp in the domain hierarchy.

IP Addresses

atcoder.jp directs to four IP numbers, which are 54.230.201.3, 54.230.201.27, 54.230.201.64 and 54.230.201.118.

Name Servers

The domain atcoder.jp is delegated to these four name servers: ns-96.awsdns-12.com, ns-890.awsdns-47.net, ns-1144.awsdns-15.org and ns-1543.awsdns-00.co.uk.

There is at least partial name server overlap between atcoder.jp and other domains — biblebee.com, equinoxfitness.com, rwapitest.com and two more among them.

All four hostnames — ns-96.awsdns-12.com, ns-890.awsdns-47.net, ns-1144.awsdns-15.org and ns-1543.awsdns-00.co.uk — resolve to two IP numbers apiece: ns-96.awsdns-12.com to 205.251.192.96 and 2600:9000:5300:6000::1; ns-890.awsdns-47.net to 205.251.195.122 and 2600:9000:5303:7a00::1; ns-1144.awsdns-15.org to 205.251.196.120 and 2600:9000:5304:7800::1; ns-1543.awsdns-00.co.uk to 205.251.198.7 and 2600:9000:5306:700::1.

Mail Servers

atcoder.jp accepts email via 7 mail servers: aspmx2.googlemail.com, aspmx3.googlemail.com, aspmx4.googlemail.com and 4 other.

atcoder.jp shares at least some of its mail servers with other domains — for example develephant.com, beyondtheinterview.com, 1620.dk and two more.

It is common to find these mail servers paired with mail servers aspmx.l.google.com, alt1.aspmx.l.google.com, alt2.aspmx.l.google.com and 3 more.

Hosts with two IP numbers each:

aspmx2.googlemail.com directs traffic to 142.250.102.27 and 2a00:1450:4025:402::1a.

aspmx3.googlemail.com directs traffic to 192.178.213.26 and 2a00:1450:4013:c1e::1b.

aspmx4.googlemail.com directs traffic to 142.251.127.27 and 2a00:1450:4025:c01::1a.

aspmx5.googlemail.com directs traffic to 172.253.152.26 and 2a00:1450:4025:c01::1b.

aspmx.l.google.com directs traffic to 192.178.223.27 and 2a00:1450:4009:c0f::1a.

alt1.aspmx.l.google.com directs traffic to 142.250.102.27 and 2a00:1450:4025:402::1b.

alt2.aspmx.l.google.com directs traffic to 192.178.213.27 and 2a00:1450:4013:c1e::1a.

Both aspmx2.googlemail.com and alt1.aspmx.l.google.com resolve to 142.250.102.27 IP addresses each.