Log File Bot Traffic Cost Analyzer

Overview

Log File Bot Traffic Cost Analyzer is a free, open-source tool for examining server logs, especially AI crawler traffic and its estimated delivery costs. It is best suited to SEO and infrastructure teams that need private log triage or want to turn crawler findings into edge rules. Its breadth is compelling, but the right analysis path depends on file size, and bot verification is not definitive.

Key features

The analyzer groups activity using 127 bot signatures and 18 browser patterns, with bandwidth, IP addresses, and TTFB by category. That detail can help teams find which crawlers consume bandwidth or crawl budget. Verification combines vendor IP data, TLS, cloud ASN signals, and behavior; the project marks its heuristics low confidence, so use the results to guide investigation, not as conclusive identification. Optional DoH reverse DNS supplies another signal.

Cost estimates use measured bytes and CDN pricing presets. Copyable rules for Cloudflare, Fastly, and AWS give teams a direct way to act on findings. Other modules cover crawl traps, render gaps, bot-versus-human performance, traffic bursts, 404 clusters, a GSC overlay, and security anomalies. CSV and PDF downloads, plus generated robots.txt, llms.txt, and crawlers.json policies, support reporting and policy work.

Input can be JSON, JSONL/NDJSON, Apache Combined, Nginx, W3C Extended, AWS ALB, Cloudflare Logpush, or gzip. The project describes processing as client-side, says logs stay on the machine, and says it uses no XHR, WebSocket, or sendBeacon; its only network request is for a demo file when the user clicks to load it. That is a strong fit for sensitive log triage, including cases where DPDP/RBI logs cannot leave the machine.

Pricing

The free plan is the whole offer described: the project is MIT-licensed and open source. The tiers are analysis routes rather than paid upgrades. Browser mode is not exact at its stated scale; larger logs call for CLI or BigQuery, so users must be comfortable with those workflows. No paid tier is described.

Platforms

The project supports Linux, self-hosted use, and web access. Cloudflare Pages is its primary deployment, GitHub Pages its backup, and a Docker run command is documented. Browser, CLI, and BigQuery analysis serve different scales: under 500 MB is sampled browser triage, 500 MB to 50 GB is exact CLI analysis, and 50 GB or more is directed to BigQuery. The browser route is useful for quick inspection, not exhaustive analysis of larger datasets.

Who it's for

Choose it if you need a free way to segment bot traffic, estimate CDN costs, assess crawl waste, or produce edge rules while keeping logs local. It is particularly relevant to teams with privacy constraints. Look elsewhere if you need browser analysis to process large logs exactly, or if low-confidence verification heuristics are insufficient for your decisions.

Pros and cons

• Pro: Broad log-format support makes it usable with several common server and CDN exports.
• Pro: Traffic breakdowns, cost estimates, edge rules, and policy exports connect analysis to practical follow-up.
• Pro: Local processing and the stated network behavior suit sensitive log review.
• Con: Browser analysis under 500 MB is sampled, so it is not a substitute for exact processing at larger sizes.
• Con: The project labels verification heuristics low confidence, which limits their value as proof of bot identity.
• Con: Exact large-file work requires the CLI or BigQuery rather than the browser workflow.

Alternatives

• SEO Log File Analysis Tools is a directory category to compare more options.
• SEO Log Auditor is another free, open-source MIT option that runs locally; choose it if its broader Linux, macOS, web, and Windows platform coverage better matches your environment.
• Spider-Lens is a free, open-source self-hosted option with no paid plans or usage limits stated; consider it if self-hosting is your priority.
• Screaming Frog SEO Log File Analyser has a free tier capped at 1,000 log event lines and one project, plus a paid plan at $139 a year; choose it if you want a bounded free trial of the workflow and a paid option.
• CrawlGenius Log Analyzer offers a free allowance of 10,000 log lines per month for one project with a seven-day visible window, plus paid plans; it may suit readers who prefer a web service with a stated monthly quota.
• LogLens offers a free plan capped at 500K requests per month for one website with 30 days of history and real-time analytics; choose it if those request and history limits suit your monitoring needs.
• SEOMER has free quick page checks with limited daily use and paid top-ups; consider it if occasional checks and a small one-time package fit better than log-file analysis.
• AuditLabs SEO Log File Analyzer is a web alternative with a paid Supporter plan; choose it if a web tool is preferable.
• Crawl Lab is a free web option with no sign-up, no paid tier, and no server-side size limit; consider it if those terms are a better fit.

Verdict

Log File Bot Traffic Cost Analyzer is a strong choice for SEO and infrastructure practitioners who want free, locally processed log triage with bot segmentation, cost estimates, and ready-to-copy edge rules. Its key advantage is combining those operational outputs with broad format support; its main reason to look elsewhere is the need for exact browser analysis at scale or stronger certainty in bot verification.