# What is Log file analysis?

Log file analysis is the practice of reading a server's raw access logs to see exactly which URLs each crawler fetched, how often, and what status code came back. It is the only fully accurate record of crawler behaviour.

## How it works

Every request to your server is logged with a timestamp, the requested URL, the response code, and the user-agent. Filtering those logs by crawler user-agent shows you the ground truth: which pages bots actually reach, which they ignore, and where they hit errors or redirects.

Verification matters because user-agents are trivially spoofed. [Real Googlebot and most AI crawlers publish IP ranges](/blogs/how-ai-crawlers-index-your-site) you can reverse-check, so you can separate genuine crawler traffic from impostors.

## Log file analysis vs the Crawl Stats report

Search Console's Crawl Stats report is a sampled, Google-only summary. Log analysis is unsampled and covers every bot, including GPTBot, PerplexityBot, and Bing. If you want to know whether AI crawlers are reaching a specific page, logs are the only source that can answer it.

## Why it matters for B2B

For GEO, logs answer the question that precedes all others: is the AI crawler even fetching this page? Before you tune a page for citations, the logs tell you whether OAI-SearchBot or PerplexityBot has visited it, how recently, and whether it got a clean 200. A page no bot has fetched is invisible regardless of how good it is.

## Frequently asked questions

**What is log file analysis?**

Log file analysis is the practice of reading a server's raw access logs to see exactly which URLs each crawler fetched, how often, and what status code came back; the only fully accurate record of crawler behaviour.

**How do you use log file analysis for SEO?**

Filter the logs by crawler user-agent to see which pages bots actually reach, spot wasted crawl on low-value URLs, find pages bots never fetch, and catch errors or redirects. Verify user-agents against published IP ranges, since they are easily spoofed.

**What tools are used for log file analysis?**

Dedicated SEO log analysers such as Screaming Frog's Log File Analyser, or general log-processing pipelines; the key is filtering by verified crawler user-agent rather than the tool itself.

**Example**

```
66.249.66.1 - - [07/Jun/2026:10:22:01] "GET /glossary/crawl-budget" 200 "Googlebot"
```

What to hunt for: bots burning requests on parameter and filter URLs, or never reaching your deep pages at all.

*Source: https://rawmktg.com/glossary/log-file-analysis · rawmktg. by Vinayak Ravi*