atcoder.jp - dns.ninja

`atcoder.jp`

DNSSEC	⚠️ Not signed
A	13.226.209.19^{🇺🇸 Amazon13.226.209.0/24 - Cloudfront}
		PTR	`server-13-226-209-19.iad61.r.cloudfront.net`
A	13.226.209.24^{🇺🇸 Amazon13.226.209.0/24 - Cloudfront}
A	13.226.209.57^{🇺🇸 Amazon13.226.209.0/24 - Cloudfront}
A	13.226.209.113^{🇺🇸 Amazon13.226.209.0/24 - Cloudfront}
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	2607:f8b0:4004:c23::1b^{🇺🇸 Google2607:f8b0:4004::/48}
			PTR	`yuiadrs-in-f27.1e100.net`
		A	64.233.180.27^{🇺🇸 Google64.233.180.0/24}
			PTR	`on-in-f27.1e100.net`
			PTR	`pe-in-f27.1e100.net`
MX	`alt1.aspmx.l.google.com`⁽²⁰⁾
		A	2800:3f0:4003:c0f::1a^{🇨🇱 Google2800:3f0:4003::/48}
		A	108.177.123.26^{🇺🇸 Google108.177.123.0/24}
			PTR	`lcscld-in-f26.1e100.net`
MX	`alt2.aspmx.l.google.com`⁽²⁰⁾
		A	2a00:1450:400b:c02::1a^{🇮🇪 Google2a00:1450:400b::/48}
			PTR	`dj-in-f26.1e100.net`
		A	172.253.116.27^{🇺🇸 Google172.253.116.0/24}
			PTR	`dj-in-f27.1e100.net`
MX	`aspmx2.googlemail.com`⁽³⁰⁾
		A	2800:3f0:4003:c0f::1a^{🇨🇱 Google2800:3f0:4003::/48}
		A	108.177.123.26^{🇺🇸 Google108.177.123.0/24}
			PTR	`lcscld-in-f26.1e100.net`
MX	`aspmx3.googlemail.com`⁽³⁰⁾
		A	2a00:1450:400b:c02::1b^{🇮🇪 Google2a00:1450:400b::/48}
			PTR	`dj-in-f27.1e100.net`
		A	172.253.116.27^{🇺🇸 Google172.253.116.0/24}
			PTR	`dj-in-f27.1e100.net`
MX	`aspmx4.googlemail.com`⁽³⁰⁾
		A	2a00:1450:4009:c0f::1a^{🇬🇧 Google2a00:1450:4009::/48}
			PTR	`yulhrs-in-f26.1e100.net`
		A	192.178.223.26^{🇺🇸 Google192.178.223.0/24}
			PTR	`yulhrs-in-f26.1e100.net`
MX	`aspmx5.googlemail.com`⁽³⁰⁾
		A	2a00:1450:400c:c23::1a^{🇧🇪 Google2a00:1450:400c::/48}
			PTR	`yubrupd-in-f26.1e100.net`
		A	172.253.157.27^{🇺🇸 Google172.253.0.0/16}
			PTR	`yubrupd-in-f27.1e100.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=1785963602

rank #46476 globally
rank #977 in the tld
📈 Tranco rank: #34,697

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

redacto.io

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

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

artdeco.co.uk

codeart.studio

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

redacto.tech

decarto.com

deactro.nl

decorat.com

doecart.com

decoart.fr

decoart.to

tradeco.com.vn

tarcode.ru

decoart.online

decorat.com.mx

cadoret.fr

cardeto.biz.id

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

DNS History

81 records (15 active, 66 former)

●NSns-1144.awsdns-15.org2017-05-24 → 2026-08-05 · 3 obs

○ 2016-07-16 04:50:00
● 2017-05-24 06:16:14
● 2026-08-05 22:12:34

●NSns-1543.awsdns-00.co.uk2017-05-24 → 2026-08-05 · 3 obs

○ 2016-07-16 04:50:00
● 2017-05-24 06:16:14
● 2026-08-05 22:12:34

●NSns-890.awsdns-47.net2017-05-24 → 2026-08-05 · 3 obs

○ 2016-07-16 04:50:00
● 2017-05-24 06:16:14
● 2026-08-05 22:12:34

●NSns-96.awsdns-12.com2017-05-24 → 2026-08-05 · 3 obs

○ 2016-07-16 04:50:00
● 2017-05-24 06:16:14
● 2026-08-05 22:12:34

○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
○ 2026-08-05 22:12:34

○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
○ 2026-08-05 22:12:34

●MXalt1.aspmx.l.google.com2015-08-13 → 2026-08-05 · 5 obs

● 2015-08-13 18:44:32
● 2018-09-08 01:26:56
○ 2026-07-25 11:20:20
● 2026-07-25 15:08:22
● 2026-08-05 22:12:34

●MXalt2.aspmx.l.google.com2015-08-13 → 2026-08-05 · 5 obs

● 2015-08-13 18:44:32
● 2018-09-08 01:26:56
○ 2026-07-25 11:20:20
● 2026-07-25 15:08:22
● 2026-08-05 22:12:34

●MXaspmx.l.google.com2015-08-13 → 2026-08-05 · 5 obs

● 2015-08-13 18:44:32
● 2018-09-08 01:26:56
○ 2026-07-25 11:20:20
● 2026-07-25 15:08:22
● 2026-08-05 22:12:34

●MXaspmx2.googlemail.com2015-08-13 → 2026-08-05 · 5 obs

● 2015-08-13 18:44:32
● 2018-09-08 01:26:56
○ 2026-07-25 11:20:20
● 2026-07-25 15:08:22
● 2026-08-05 22:12:34

●MXaspmx3.googlemail.com2015-08-13 → 2026-08-05 · 5 obs

● 2015-08-13 18:44:32
● 2018-09-08 01:26:56
○ 2026-07-25 11:20:20
● 2026-07-25 15:08:22
● 2026-08-05 22:12:34

●MXaspmx4.googlemail.com2015-08-13 → 2026-08-05 · 5 obs

● 2015-08-13 18:44:32
● 2018-09-08 01:26:56
○ 2026-07-25 11:20:20
● 2026-07-25 15:08:22
● 2026-08-05 22:12:34

●MXaspmx5.googlemail.com2015-08-13 → 2026-08-05 · 5 obs

● 2015-08-13 18:44:32
● 2018-09-08 01:26:56
○ 2026-07-25 11:20:20
● 2026-07-25 15:08:22
● 2026-08-05 22:12:34

○A108.156.85.1092026-03-31 → 2026-08-05 · 82 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 23:38:46
○ 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
○ 2026-05-13 22:13:06
● 2026-05-14 15:42:52
○ 2026-05-14 23:12:54
○ 2026-05-30 20:10:00
● 2026-05-31 12:46:18
● 2026-06-01 11:56:02
○ 2026-06-01 22:19:22
○ 2026-06-10 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
● 2026-07-01 02:38:56
○ 2026-07-01 18:26:46
● 2026-07-02 21:06:38
○ 2026-07-03 06:44:10
● 2026-07-03 18:37:24
○ 2026-07-04 03:56:42
● 2026-07-04 06:00:50
○ 2026-07-05 01:48:26
● 2026-07-07 15:52:34
○ 2026-07-07 21:48:58
● 2026-07-08 00:16:38
○ 2026-07-10 17:28:36
● 2026-07-11 05:20:16
○ 2026-07-11 21:08:16
● 2026-07-11 23:36:52
○ 2026-07-12 06:18:12
● 2026-07-12 06:51:58
○ 2026-07-12 10:31:42
● 2026-07-12 11:49:26
○ 2026-07-13 13:12:42
● 2026-07-13 13:50:26
○ 2026-07-14 01:54:16
● 2026-07-15 11:25:32
○ 2026-07-15 17:15:52
● 2026-07-16 23:42:36
○ 2026-07-17 04:44:14
● 2026-07-17 14:02:48
○ 2026-07-18 06:47:46
● 2026-07-19 01:06:00
○ 2026-07-19 19:55:34
● 2026-07-20 04:33:30
○ 2026-07-22 11:20:00
● 2026-07-23 11:23:12
○ 2026-07-24 16:22:14
● 2026-07-24 23:07:16
○ 2026-07-25 11:20:20
● 2026-07-26 00:44:04
○ 2026-07-26 04:53:52
● 2026-07-26 12:19:12
○ 2026-07-26 20:16:18
● 2026-07-27 21:08:42
○ 2026-07-28 06:18:38
● 2026-07-28 17:02:44
○ 2026-07-28 19:25:04
● 2026-07-31 03:43:12
○ 2026-08-01 21:10:32
● 2026-08-02 08:33:40
○ 2026-08-02 19:27:40
● 2026-08-02 23:05:16
○ 2026-08-03 02:35:16
● 2026-08-04 04:16:26
○ 2026-08-04 08:49:42
● 2026-08-04 14:59:36
○ 2026-08-05 09:04:02
● 2026-08-05 11:52:32
○ 2026-08-05 22:12:32
○ 2026-08-05 22:12:34

○A108.156.85.1112026-03-31 → 2026-08-05 · 82 obs

○A108.156.85.462026-03-31 → 2026-08-05 · 82 obs

○A108.156.85.892026-03-31 → 2026-08-05 · 82 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
○ 2026-08-05 22:12:34

○A13.224.125.1042026-07-17 → 2026-07-17 · 4 obs

○ 2026-07-16 23:42:36
● 2026-07-17 04:44:14
○ 2026-07-17 14:02:48
○ 2026-08-05 22:12:34

○A13.224.125.32026-07-17 → 2026-07-17 · 4 obs

○ 2026-07-16 23:42:36
● 2026-07-17 04:44:14
○ 2026-07-17 14:02:48
○ 2026-08-05 22:12:34

○A13.224.125.322026-07-17 → 2026-07-17 · 4 obs

○ 2026-07-16 23:42:36
● 2026-07-17 04:44:14
○ 2026-07-17 14:02:48
○ 2026-08-05 22:12:34

○A13.224.125.952026-07-17 → 2026-07-17 · 4 obs

○ 2026-07-16 23:42:36
● 2026-07-17 04:44:14
○ 2026-07-17 14:02:48
○ 2026-08-05 22:12:34

●A13.226.209.1132026-02-14 → 2026-08-05 · 57 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
● 2026-03-01 05:17:48
○ 2026-03-01 14:41:46
● 2026-03-03 00:36:20
○ 2026-03-04 04:08:04
○ 2026-03-20 11:16:46
● 2026-03-21 15:01:56
○ 2026-03-21 21:29:32
○ 2026-06-10 03:16:54
● 2026-06-11 08:21:52
○ 2026-06-12 06:09:48
○ 2026-06-13 11:08:06
● 2026-06-14 15:00:02
○ 2026-06-15 17:43:46
○ 2026-06-17 23:29:58
● 2026-06-18 19:45:00
● 2026-06-19 14:27:40
○ 2026-06-19 15:06:34
● 2026-06-19 15:36:44
○ 2026-06-19 17:20:36
● 2026-06-24 06:01:16
○ 2026-06-24 08:51:56
● 2026-06-24 15:16:56
○ 2026-06-24 16:18:42
● 2026-06-25 11:43:40
○ 2026-06-25 15:46:32
● 2026-06-26 05:01:18
○ 2026-06-26 12:25:36
● 2026-06-27 05:01:24
○ 2026-06-27 11:58:24
● 2026-06-27 15:13:36
○ 2026-06-27 15:47:54
● 2026-06-30 00:05:34
○ 2026-06-30 02:36:44
● 2026-06-30 05:07:56
○ 2026-06-30 15:37:32
● 2026-07-01 23:30:46
○ 2026-07-02 04:01:04
● 2026-07-04 04:47:16
○ 2026-07-04 06:00:50
● 2026-07-05 01:48:26
○ 2026-07-05 04:13:32
● 2026-07-07 21:48:58
○ 2026-07-07 23:38:30
● 2026-07-12 10:31:42
○ 2026-07-12 11:49:26
● 2026-08-03 02:35:16
○ 2026-08-03 03:44:38
● 2026-08-04 12:40:24
○ 2026-08-04 14:59:36
● 2026-08-05 22:12:32
● 2026-08-05 22:12:34

●A13.226.209.192026-02-14 → 2026-08-05 · 57 obs

●A13.226.209.242026-02-14 → 2026-08-05 · 57 obs

●A13.226.209.572026-02-14 → 2026-08-05 · 57 obs

○A13.33.235.1142026-03-25 → 2026-07-18 · 14 obs

○ 2026-03-21 21:29:32
● 2026-03-25 11:25:00
○ 2026-03-25 13:48:44
● 2026-07-11 21:08:16
○ 2026-07-11 23:36:52
● 2026-07-12 06:18:12
○ 2026-07-12 06:51:58
● 2026-07-14 01:54:16
○ 2026-07-15 11:25:32
● 2026-07-15 21:34:56
○ 2026-07-16 23:42:36
● 2026-07-18 19:57:24
○ 2026-07-19 01:06:00
○ 2026-08-05 22:12:34

○A13.33.235.1272026-03-25 → 2026-07-18 · 14 obs

○A13.33.235.352026-03-25 → 2026-07-18 · 14 obs

○A13.33.235.682026-03-25 → 2026-07-18 · 14 obs

○A13.35.107.32026-07-13 → 2026-07-30 · 20 obs

○ 2026-07-12 11:49:26
● 2026-07-13 13:12:42
○ 2026-07-13 13:50:26
● 2026-07-15 17:15:52
○ 2026-07-15 21:34:56
● 2026-07-18 06:47:46
○ 2026-07-18 19:57:24
● 2026-07-22 11:20:00
○ 2026-07-22 18:56:16
● 2026-07-24 16:22:14
○ 2026-07-24 20:22:48
● 2026-07-25 15:08:22
○ 2026-07-26 00:44:04
● 2026-07-26 20:16:18
○ 2026-07-27 21:08:42
● 2026-07-28 22:17:34
○ 2026-07-29 05:57:58
● 2026-07-30 08:47:06
○ 2026-07-30 12:31:12
○ 2026-08-05 22:12:34

○A13.35.107.622026-07-13 → 2026-07-30 · 20 obs

○A13.35.107.72026-07-13 → 2026-07-30 · 20 obs

○A13.35.107.982026-07-13 → 2026-07-30 · 20 obs

○A18.155.129.412026-07-26 → 2026-07-28 · 8 obs

○ 2026-07-26 00:44:04
● 2026-07-26 04:53:52
○ 2026-07-26 12:19:12
● 2026-07-28 13:19:16
○ 2026-07-28 17:02:44
● 2026-07-28 21:30:36
○ 2026-07-28 22:17:34
○ 2026-08-05 22:12:34

○A18.155.129.842026-07-26 → 2026-07-28 · 8 obs

○ 2026-07-26 00:44:04
● 2026-07-26 04:53:52
○ 2026-07-26 12:19:12
● 2026-07-28 13:19:16
○ 2026-07-28 17:02:44
● 2026-07-28 21:30:36
○ 2026-07-28 22:17:34
○ 2026-08-05 22:12:34

○A18.155.129.892026-07-26 → 2026-07-28 · 8 obs

○ 2026-07-26 00:44:04
● 2026-07-26 04:53:52
○ 2026-07-26 12:19:12
● 2026-07-28 13:19:16
○ 2026-07-28 17:02:44
● 2026-07-28 21:30:36
○ 2026-07-28 22:17:34
○ 2026-08-05 22:12:34

○A18.155.129.92026-07-26 → 2026-07-28 · 8 obs

○ 2026-07-26 00:44:04
● 2026-07-26 04:53:52
○ 2026-07-26 12:19:12
● 2026-07-28 13:19:16
○ 2026-07-28 17:02:44
● 2026-07-28 21:30:36
○ 2026-07-28 22:17:34
○ 2026-08-05 22:12:34

○A18.161.21.1162026-04-24 → 2026-08-02 · 26 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 18:02:06
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● 2026-04-27 13:39:04
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● 2026-05-09 19:27:42
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● 2026-08-02 20:20:32
○ 2026-08-02 23:05:16
○ 2026-08-05 22:12:34

○A18.161.21.432026-04-24 → 2026-08-02 · 26 obs

○A18.161.21.712026-04-24 → 2026-08-02 · 26 obs

○A18.161.21.772026-04-24 → 2026-08-02 · 26 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
○ 2026-08-05 22:12:34

○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
○ 2026-08-05 22:12:34

○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
○ 2026-08-05 22:12:34

○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
○ 2026-08-05 22:12:34

○A18.244.202.402026-04-03 → 2026-07-30 · 56 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
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● 2026-04-05 00:55:36
○ 2026-04-05 07:17:12
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● 2026-04-08 03:24:30
○ 2026-04-08 15:43:32
● 2026-04-09 04:20:28
○ 2026-04-09 07:48:54
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● 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
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● 2026-06-19 15:06:34
● 2026-06-19 17:20:36
○ 2026-06-19 21:26:48
● 2026-06-20 07:38:42
○ 2026-06-20 12:30:06
● 2026-06-23 08:28:10
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● 2026-06-24 08:51:56
○ 2026-06-24 12:18:04
● 2026-06-24 16:18:42
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● 2026-06-25 10:38:54
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● 2026-06-26 12:25:36
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● 2026-06-27 01:09:28
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● 2026-06-29 17:23:20
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● 2026-06-30 02:36:44
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● 2026-07-02 04:01:04
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● 2026-07-28 06:18:38
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● 2026-07-28 19:25:04
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● 2026-07-29 18:57:56
○ 2026-07-30 08:47:06
● 2026-07-30 12:31:12
○ 2026-07-31 03:43:12
○ 2026-08-05 22:12:34

○A18.244.202.512026-04-03 → 2026-07-30 · 56 obs

○A18.244.202.752026-04-03 → 2026-07-30 · 56 obs

○A18.244.202.792026-04-03 → 2026-07-30 · 56 obs

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

○ 2026-06-01 22:19:22
● 2026-06-03 04:31:02
○ 2026-06-03 06:03:22
○ 2026-06-03 20:13:38
● 2026-06-03 22:43:52
○ 2026-06-04 00:09:20
○ 2026-08-05 22:12:34

○A18.67.233.1092026-06-03 → 2026-06-03 · 7 obs

○ 2026-06-01 22:19:22
● 2026-06-03 04:31:02
○ 2026-06-03 06:03:22
○ 2026-06-03 20:13:38
● 2026-06-03 22:43:52
○ 2026-06-04 00:09:20
○ 2026-08-05 22:12:34

○A18.67.233.272026-06-03 → 2026-06-03 · 7 obs

○ 2026-06-01 22:19:22
● 2026-06-03 04:31:02
○ 2026-06-03 06:03:22
○ 2026-06-03 20:13:38
● 2026-06-03 22:43:52
○ 2026-06-04 00:09:20
○ 2026-08-05 22:12:34

○A18.67.233.862026-06-03 → 2026-06-03 · 7 obs

○ 2026-06-01 22:19:22
● 2026-06-03 04:31:02
○ 2026-06-03 06:03:22
○ 2026-06-03 20:13:38
● 2026-06-03 22:43:52
○ 2026-06-04 00:09:20
○ 2026-08-05 22:12:34

○A3.162.112.162026-04-19 → 2026-04-19 · 4 obs

○ 2026-04-18 22:59:02
● 2026-04-19 19:41:18
○ 2026-04-22 00:48:16
○ 2026-08-05 22:12:34

○A3.162.112.262026-04-19 → 2026-04-19 · 4 obs

○ 2026-04-18 22:59:02
● 2026-04-19 19:41:18
○ 2026-04-22 00:48:16
○ 2026-08-05 22:12:34

○A3.162.112.682026-04-19 → 2026-04-19 · 4 obs

○ 2026-04-18 22:59:02
● 2026-04-19 19:41:18
○ 2026-04-22 00:48:16
○ 2026-08-05 22:12:34

○A3.162.112.742026-04-19 → 2026-04-19 · 4 obs

○ 2026-04-18 22:59:02
● 2026-04-19 19:41:18
○ 2026-04-22 00:48:16
○ 2026-08-05 22:12:34

○A3.169.231.1122026-02-24 → 2026-08-05 · 54 obs

○ 2026-02-19 13:08:28
● 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
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● 2026-03-16 03:11:34
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● 2026-03-20 11:16:46
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● 2026-03-28 09:37:26
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● 2026-07-03 06:44:10
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● 2026-07-29 16:59:32
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● 2026-08-01 21:10:32
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● 2026-08-02 19:27:40
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● 2026-08-03 03:44:38
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● 2026-08-04 08:49:42
○ 2026-08-04 12:40:24
● 2026-08-05 09:04:02
○ 2026-08-05 11:52:32
○ 2026-08-05 22:12:34

○A3.169.231.452026-02-24 → 2026-08-05 · 54 obs

○A3.169.231.482026-02-24 → 2026-08-05 · 54 obs

○A3.169.231.552026-02-24 → 2026-08-05 · 54 obs

○A3.170.185.102026-05-19 → 2026-07-01 · 29 obs

○ 2026-05-18 22:26:06
● 2026-05-19 09:14:32
● 2026-05-19 12:38:08
○ 2026-05-19 16:22:16
○ 2026-05-19 18:04:40
● 2026-05-19 19:43:34
● 2026-05-24 20:24:08
○ 2026-05-25 02:49:38
● 2026-05-25 12:05:16
● 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
● 2026-06-04 03:46:54
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● 2026-06-05 01:13:08
● 2026-06-07 11:28:28
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● 2026-06-07 20:07:30
● 2026-06-08 07:39:54
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● 2026-06-30 15:37:32
○ 2026-06-30 18:41:46
● 2026-07-01 18:26:46
○ 2026-07-01 23:30:46
○ 2026-08-05 22:12:34

○A3.170.185.872026-05-19 → 2026-07-01 · 29 obs

○A3.170.185.882026-05-19 → 2026-07-01 · 29 obs

○A3.170.185.972026-05-19 → 2026-07-01 · 29 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
○ 2026-08-05 22:12:34

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

○ 2026-03-06 18:07:04
● 2026-03-08 00:13:48
○ 2026-03-08 10:16:58
○ 2026-03-08 15:54:16
● 2026-03-08 17:23:56
○ 2026-03-08 18:22:38
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● 2026-03-29 22:43:20
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● 2026-04-02 06:31:10
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● 2026-04-05 07:17:12
● 2026-04-05 20:25:44
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○ 2026-05-20 13:23:58
● 2026-05-20 18:10:04
○ 2026-05-20 23:21:52
○ 2026-08-05 22:12:34

○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 → 2026-06-30 · 47 obs

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

○A54.230.201.272026-04-23 → 2026-06-30 · 47 obs

○A54.230.201.32026-04-23 → 2026-06-30 · 47 obs

○A54.230.201.642026-04-23 → 2026-06-30 · 47 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
○ 2026-08-05 22:12:34

○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
○ 2026-08-05 22:12:34

○A99.86.91.302026-02-19 → 2026-04-22 · 26 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
○ 2026-03-06 18:07:04
○ 2026-03-09 06:48:08
● 2026-03-12 05:55:12
● 2026-03-13 07:09:24
○ 2026-03-14 11:40:54
○ 2026-03-16 03:11:34
● 2026-03-17 12:33:22
● 2026-03-18 13:29:54
○ 2026-03-20 08:14:06
● 2026-03-21 21:29:32
● 2026-03-25 13:48:44
○ 2026-03-28 09:37:26
○ 2026-04-08 03:24:30
● 2026-04-09 07:48:54
○ 2026-04-10 09:03:20
○ 2026-04-19 19:41:18
● 2026-04-22 00:48:16
● 2026-04-22 15:43:14
○ 2026-04-23 11:39:44
○ 2026-08-05 22:12:34

○A99.86.91.512026-02-19 → 2026-04-22 · 26 obs

○A99.86.91.92026-02-19 → 2026-04-22 · 26 obs

○A99.86.91.982026-02-19 → 2026-04-22 · 26 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:205.251.196.120

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: 1743ms | Queries: -

📄 Records

Type	Count	Sample Data
A	4	`13.226.209.24, 13.226.209.19...`
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 13.226.209.19, 13.226.209.24, 13.226.209.57 and 13.226.209.113.

Among the host names that share IP numbers with atcoder.jp are d2xk9y90ff3xxy.cloudfront.net, masoniccivility.org, ca1801f7ee05.cdn4.forter.com and two others.

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 108.177.123.26 and 2800:3f0:4003:c0f::1a.

aspmx3.googlemail.com directs traffic to 172.253.116.27 and 2a00:1450:400b:c02::1b.

aspmx4.googlemail.com directs traffic to 192.178.223.26 and 2a00:1450:4009:c0f::1a.

aspmx5.googlemail.com directs traffic to 172.253.157.27 and 2a00:1450:400c:c23::1a.

aspmx.l.google.com directs traffic to 64.233.180.27 and 2607:f8b0:4004:c23::1b.

alt1.aspmx.l.google.com directs traffic to 108.177.123.26 and 2800:3f0:4003:c0f::1a.

alt2.aspmx.l.google.com directs traffic to 172.253.116.27 and 2a00:1450:400b:c02::1a.

Both aspmx2.googlemail.com and alt1.aspmx.l.google.com resolve to 2800:3f0:4003:c0f::1a IP addresses each.

Both aspmx2.googlemail.com and alt1.aspmx.l.google.com resolve to 108.177.123.26 IP addresses each.

Both aspmx3.googlemail.com and alt2.aspmx.l.google.com resolve to 172.253.116.27 IP addresses each.