Definition
Cloudflare Workers is a serverless platform that runs JavaScript across Cloudflare's global network (over 300 points of presence). For SEO, Workers allow you to intercept and modify HTTP requests and responses in real time. SEO use cases include injecting hreflang tags, managing massive redirect tables, adding structured data, modifying meta tags, pre-rendering for bots, and running SEO A/B tests. Combined with Workers KV (a distributed key-value store), you can manage redirect tables with millions of entries at sub-millisecond latency.
Key Points
- Runs code at the edge with minimal latency across 300+ data centers
- Allows modifying HTTP responses without touching the origin server
- Workers KV enables managing millions of redirects with sub-millisecond latency
Practical Examples
Pre-rendering for bots
A SPA site uses a Cloudflare Worker to detect search engine bot user-agents and serve them a pre-rendered version of the page, improving indexation.
Title tag A/B testing
An SEO team deploys a Worker that modifies title tags on certain pages for 50% of Googlebot requests, enabling CTR impact testing in SERPs.
Frequently Asked Questions
The free Cloudflare Workers plan offers 100,000 requests per day, which is sufficient for many SEO use cases. Paid plans start at $5/month for 10 million requests.
Yes, modifications made by a Cloudflare Worker are visible to Googlebot just like to any other visitor, because they are applied before the response reaches the client. That is precisely the advantage for SEO.
Go Further with LemmiLink
Discover how LemmiLink can help you put these SEO concepts into practice.
Last updated: 2026-02-07