Overview

Interlink finds orphaned and under-linked posts, flags broken internal links, and recommends link counts. That makes it useful when a site’s archive has grown without a consistent linking structure. Suggestions require approval; when links are inserted, the plugin only turns existing text into links rather than writing new sentences, and supports undo. This is a cautious approach to automation, though it leaves final decisions with the editor.

By default, analysis runs locally against the site’s WordPress database, with no external requests or tracking. Optional AI relevance uses the site owner’s own OpenAI or Google Gemini API key and sends post titles and text, plus candidate titles, directly to that provider. The local default suits sites that want to keep analysis on-site; enabling AI means accepting that additional data flow.

Key features

The audit reports total internal links, orphaned posts, under-linked and well-linked posts, and recommended link counts. Anchor-text diversity reporting, cornerstone-content prioritization, and an editor meta box showing links and their status help editors assess coverage as well as individual recommendations. Rank Math focus keywords can be used as preferred anchors.

Auto-link rules map keywords to URLs, with optional restrictions by shared category or tag and an option to apply rules when a post is saved. That can make recurring links more consistent, but automatic insertion is not the same as suggestion-only editing; sites that want tighter control should review their rules and use the approval-first workflow for suggestions.

CSV export, weekly scheduled scans, role control, and settings import and export support ongoing audits and team administration. Optional integrations include OpenAI, Google Gemini, and Google Search Console. Interlink has no front-end footprint: assets load only on admin screens, and the link map is cached in a small table. That design keeps its work focused on the WordPress back end.

Pricing

Free: 0.00 USD per free (billed Free; WordPress plugin · no signup · WordPress 5.5+ · PHP 7.4+). The plan is free to install and use, with no signup. It is a strong fit for WordPress site owners who want audits, link suggestions, and rules without a subscription. The plan details provide no paid tier to compare, so there is no stated upgrade path or paid-plan quota to weigh.

Platforms

Interlink is a self-hosted WordPress plugin. It requires WordPress 5.5 or higher and PHP 7.4 or higher, and is tested up to WordPress 7.1.2. Install it from the WordPress Plugins screen or upload it to /wp-content/plugins/, then activate it and rescan the site. Its WordPress-specific setup makes it unsuitable for sites not running WordPress.

Who it's for

The maker highlights sites with 20 or more posts, old archives, low visibility, siloed content, or un-audited broken links. Those are sensible use cases for a tool that surfaces gaps and lets an editor decide what to fix. Smaller sites may have less need for its audit and scheduling features. The WordPress listing provides a support forum and currently has no submitted reviews.

Pros and cons

Pros: The free plan has no signup, while local default analysis avoids external requests and tracking.
Pros: Approval-first suggestions, existing-text-only link insertion, and undo give editors safeguards against unwanted content changes.
Pros: Audit reports, scheduled scans, exports, role control, and keyword-based rules cover both diagnosis and routine maintenance.
Cons: Optional AI relevance sends post text and titles, plus candidate titles, to OpenAI or Google Gemini, so it changes the data-flow trade-off.
Cons: The plugin requires a compatible WordPress and PHP installation; it is not a general-purpose service for other platforms.
Cons: The WordPress listing currently has no submitted reviews, leaving no user-review record to consult.

Alternatives

For a broader comparison, see Internal Linking Tools.

Link Whisper is worth considering if you want a freemium WordPress option with a free trial; its free plan offers manually inserted outbound link suggestions.
Linkagent may suit teams wanting self-hosted infrastructure or API access. Its Self-hosted plan is free forever under AGPL-3.0 and requires your infrastructure.
LinkBoss is a web-based option with a free plan that includes 50 credits on signup for one site, without a credit card.
Linkbot is a web-based alternative whose free Starter plan covers one website property and up to 1,000 URLs, with reports and diagnostics but no automated linking or ongoing sync.
Uix Page Builder is another free WordPress plugin option.
Orbis Internal Link Assistant offers one-time-priced plans for one site, five sites, or unlimited sites, which may suit buyers who prefer a per-purchase license structure.
LinkNavigator is another web-based freemium option.
Automatic Internal Links for SEO is another web-based freemium option.

Verdict

Choose Interlink if you run a WordPress site with a growing or neglected archive and want a free way to identify linking gaps while keeping editorial approval in the process. Its local-by-default analysis and non-destructive workflow are the clearest reasons to choose it. Look elsewhere if you do not use WordPress, or if you need a web-based service rather than a plugin tied to your site.

	Interlink	redCacti
Free plan	Yes	Yes
Free trial	No	Yes
Paid from	Free	$19/mo
Open source	No	No
Platforms	self-hosted, Web	Web
Free plan	Yes	Yes
Platform	wordpress	hosted
Link suggestions	Yes	Yes
Automatic linking	Yes	No
Orphan page detection	Yes	Yes
Bulk link editing	Yes	—
Paid from	—	19 /mo
Crawl limit	—	10,000 pages

Interlink vs redCacti

Interlink

redCacti