Class C IP Checker

Free Class C IP Checker — Analyze IP Diversity for Link Building

In SEO link building, the diversity of your backlinks matters. Google evaluates not just how many sites link to you, but where those sites are hosted. Multiple links from sites on the same Class C IP address block (the same first three IP octets) signal that those sites may be owned or controlled by the same entity — reducing the value Google assigns to those links. This free Class C IP Checker shows you the Class C block for any list of domains, helping you assess true backlink diversity and identify potentially risky link patterns.

Enter a list of domains (one per line) and the tool resolves each to its IP address and shows the Class C block (first three octets). Domains sharing the same Class C block are highlighted, showing you which links come from the same IP neighborhood.

This is particularly useful when evaluating link prospects for outreach, auditing your existing backlink profile, or investigating a competitor's link network for PBN (private blog network) patterns.

Class C IP and Link Building

Backlink diversity. A healthy backlink profile has links from many different Class C IP ranges. Dozens of links all from the same /24 block look unnatural to Google.

PBN detection. Private blog networks often host multiple sites on the same server or hosting provider. Shared Class C blocks are one signal used to identify PBN footprints.

Link audit. Before a link building campaign, check if target sites share IP blocks with sites you already have links from. Prioritize diverse IP ranges.

Competitor analysis. Check if a competitor's links come from a diverse range of IPs or from a concentrated block, indicating artificial link building patterns.

Related Tools

• Backlink Checker – Check backlinks for any domain.
• Reverse IP Checker – Find all domains hosted on the same IP.
• Domain to IP – Convert domain names to IP addresses.

Frequently Asked Questions