codeforces.com Review

TitletagDescriptiontaglanguage
Codeforces English
Alexarank
3133
Ip adress172.67.68.254Nameserverfred.ns.cloudflare.com
jean.ns.cloudflare.com
Status code200
robots.txt -http://codeforces.com/robots.txt
 # As a condition of accessing this website, you agree to abide by the following
# content signals:

# (a)  If a Content-Signal = yes, you may collect content for the corresponding
#      use.
# (b)  If a Content-Signal = no, you may not collect content for the
#      corresponding use.
# (c)  If the website operator does not include a Content-Signal for a
#      corresponding use, the website operator neither grants nor restricts
#      permission via Content-Signal with respect to the corresponding use.

# The content signals and their meanings are:

# search:   building a search index and providing search results (e.g., returning
#           hyperlinks and short excerpts from your website's contents). Search does not
#           include providing AI-generated search summaries.
# ai-input: inputting content into one or more AI models (e.g., retrieval
#           augmented generation, grounding, or other real-time taking of content for
#           generative AI search answers).
# ai-train: training or fine-tuning AI models.

# ANY RESTRICTIONS EXPRESSED VIA CONTENT SIGNALS ARE EXPRESS RESERVATIONS OF
# RIGHTS UNDER ARTICLE 4 OF THE EUROPEAN UNION DIRECTIVE 2019/790 ON COPYRIGHT
# AND RELATED RIGHTS IN THE DIGITAL SINGLE MARKET.

# BEGIN Cloudflare Managed content

User-agent: *
Content-Signal: search=yes,ai-train=no
Allow: /

User-agent: Amazonbot
Disallow: /

User-agent: Applebot-Extended
Disallow: /

User-agent: Bytespider
Disallow: /

User-agent: CCBot
Disallow: /

User-agent: ClaudeBot
Disallow: /

User-agent: Google-Extended
Disallow: /

User-agent: GPTBot
Disallow: /

User-agent: meta-externalagent
Disallow: /

# END Cloudflare Managed Content

HTTP/1.1 301 Moved Permanently
Date: Sat, 07 Feb 2026 06:10:09 GMT
Content-Length: 0
Connection: keep-alive
Location: https://codeforces.com/
Vary: accept-encoding
Report-To: {"group":"cf-nel","max_age":604800,"endpoints":[{"url":"https://a.nel.cloudflare.com/report/v4?s=8saWRofoZrt%2B8sTj%2BoHJ4X%2FxhDYS9Ps5SXqGkduvsdVLh81QONUNthAtvBjHNcmQlhWr1YOIwIYB3hQP%2BSgSgc65Py2rBWbFwHO9114%3D"}]}
Nel: {"report_to":"cf-nel","success_fraction":0.0,"max_age":604800}
Server-Timing: cfEdge;dur=6,cfOrigin;dur=0
Server: cloudflare
CF-RAY: 9ca0b8fb3dbad510-NRT
alt-svc: h3=":443"; ma=86400

HTTP/1.1 200 OK
Date: Sat, 07 Feb 2026 06:10:10 GMT
Content-Type: text/html;charset=UTF-8
Transfer-Encoding: chunked
Connection: keep-alive
Server: cloudflare
Nel: {"report_to":"cf-nel","success_fraction":0.0,"max_age":604800}
Vary: Accept-Encoding
vary: accept-encoding
Set-Cookie: JSESSIONID=0880C45F1CB6EE588575E96D2CD2E713; Path=/; HttpOnly; SameSite=Lax
Set-Cookie: 39ce7=CFLP4M9f; Max-Age=1000000; Path=/; Secure=false; SameSite=Lax
Set-Cookie: 39ce7=CFLP4M9f; Max-Age=1000000; Expires=Wed, 18 Feb 2026 19:56:50 GMT; Path=/; SameSite=Lax
X-Robots-Tag: noai
X-Robots-Tag: noai
X-Req-Id: neo:9ca0b8fb7a2a4a26-NRT:/
Cache-Control: private,no-cache,no-store,max-age=0,must-revalidate
Expires: -1
Pragma: no-cache
Strict-Transport-Security: max-age=86400
X-XSS-Protection: 1; mode=block
X-Frame-Options: sameorigin
X-Content-Type-Options: nosniff
Report-To: {"group":"cf-nel","max_age":604800,"endpoints":[{"url":"https://a.nel.cloudflare.com/report/v4?s=xxfpGBMhPb71T%2BerY1rGjh%2Brjjuo6rQz8Yybx%2BCz8gocK8z90UH8A8c2lnKY8sMMoZcv6VFg6nW60GClsJ75rUa35evBE%2B7XXhBWFSQ%3D"}]}
cf-cache-status: DYNAMIC
Server-Timing: cfCacheStatus;desc="DYNAMIC"
Server-Timing: cfEdge;dur=5,cfOrigin;dur=336
Content-Encoding: br
CF-RAY: 9ca0b8fb7a2a4a26-NRT
alt-svc: h3=":443"; ma=86400

iframe