反向 DNS 查询
查找任意 IP 地址背后的主机名(PTR 记录)。采用实时 DNS-over-HTTPS 查询 — 而非缓存数据库,因此结果反映网络运营商当前发布的最新信息。
请在上方输入 IP 地址,然后点击"查询"。
Reverse DNS maps an IP address back to a hostname using a PTR (pointer) record — the inverse of the A/AAAA record that maps a hostname to an IP. A PTR record is set by whoever controls the IP block (the hosting provider or ISP), not the domain owner, so it often reveals infrastructure rather than a public-facing site name.
Why it matters
- Mail deliverability
- Most receiving mail servers check that a sending IP has a PTR record that resolves back to a hostname in a matching domain (forward-confirmed rDNS). Missing or mismatched PTR records are a common reason legitimate mail lands in spam.
- Security investigation
- A PTR record often names the hosting provider or cloud region directly (e.g.
ec2-…amazonaws.com), a fast way to tell hosting infrastructure apart from a residential or business connection. - Log enrichment
- Adding a resolved hostname to access logs or SIEM events gives an analyst more context than a bare IP, especially for infrastructure that rotates addresses but keeps a stable naming convention.
常见问题
hostname: null;这本身并不可疑。in-addr.arpa 换成了 ip6.arpa,系统会自动处理。关于此工具
反向 DNS 通过 PTR 记录将 IP 地址映射回主机名。本工具可对任意 IPv4 或 IPv6 地址执行该查询,并显示地址所有者发布的主机名(如果有)。
工作原理
查询通过 DNS-over-HTTPS 实时发起,因此结果反映的是 DNS 的当前状态,而不是缓存的快照。结果即返回的原始 PTR 值,不做猜测,也不拼凑其他数据。
注意事项
许多地址根本没有 PTR 记录;即使有,也由控制该地址段的一方设置,因此主机名只是线索,不能证明身份。看起来可信的 PTR 记录,还应通过检查该主机名正向解析是否指向同一地址来加以确认。
常见用途
反向 DNS 常用于识别邮件服务器、更轻松地阅读服务器日志、识别冒用知名名称的爬虫,以及在接收服务器要求 PTR 匹配时排查邮件送达问题。
相关工具: 托管域名查询 · IP whois 查询 · ASN 查询 · IP 查询