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Internal Link Depth & PageRank Flow Modeller

Interactive calculator to model internal crawl depth distribution, calculate PageRank decay across click tiers, and estimate crawl budget waste.

By Gordon Geraghty·MIT Licence·Updated: 21 August 2026·INTERMEDIATE·GitHub Mirror ↗

Internal Link Depth & PageRank Flow Modeller

SEO Architecture Engine

Evaluate your internal crawl depth distribution, calculate PageRank decay across click tiers, and identify crawl budget waste from deep URLs or orphaned pages.

Site Architecture Page Counts

Crawl Architecture & Equity Summary

Crawl Depth Score
73.78%
Pages at 3 clicks or fewer
Crawl Budget Waste
26.22%
113 deep or orphaned URLs
Total Site Pages
431
8 orphaned (1.86%)
Architecture Status
NEEDS IMPROVEMENT
Structural equity health
PageRank Flow & Tier Distribution
Depth 0 (Home Page)1 pages (0.23%) : 1x PR
Depth 1 (Primary Hubs)12 pages (2.78%) : 0.85x PR
Depth 2 (Subcategories)65 pages (15.08%) : 0.7225x PR
Depth 3 (Standard Pages)240 pages (55.68%) : 0.6141x PR
Depth 4 (Deep Architecture)80 pages (18.56%) : 0.522x PR
Depth 5 (Deep Architecture)25 pages (5.8%) : 0.4437x PR
Architecture Recommendations
  • Resolve 8 orphaned URLs (1.9% of site) by linking them from contextual category hubs or HTML sitemaps.
  • Flatten site hierarchy to bring 105 deep URLs (24.4%) to click depth 3 or fewer using breadcrumbs and faceted filters.
  • Deep pages suffer from exponential PageRank decay. Boost internal link equity via related content modules and author entity links.
Built by Gordon Geraghty, Head of PerformanceZero Data Sent to Server

Why Crawl Depth Governs Indexation Frequency

Search engine crawlers allocate finite resources to each domain. Pages located 4 or more clicks from the home page receive exponential reductions in internal link equity and are crawled less frequently. Keeping key content within 3 clicks ensures consistent indexation.

Implementation Code & Script

PageRank Decay Calculation Enginepagerank-flow.tstypescript

Calculates exponential PageRank decay per crawl tier based on standard 0.85 damping factor.

export function calculateTierPageRank(depth: number, damping: number = 0.85): number {
  return Math.pow(damping, Math.max(0, depth));
}

export function evaluateCrawlBudgetHealth(pagesAtDepth4Plus: number, totalPages: number): number {
  if (totalPages === 0) return 0;
  return Number(((pagesAtDepth4Plus / totalPages) * 100).toFixed(2));
}

How to cite and attribute this tool

MIT Licence

This resource is free, open and un-gated under the MIT Open Source Licence. You are encouraged to use, integrate and cite it with attribution:

Geraghty, G. (2026). Internal Link Depth & PageRank Flow Modeller. Gordon Geraghty Resources Hub. https://gordongeraghty.com/resources/technical-seo/internal-link-depth-modeler
BibTeX Format
@misc{geraghty_internal_link_depth_modeler,
  author = {Geraghty, Gordon},
  title = {Internal Link Depth & PageRank Flow Modeller},
  year = {2026},
  url = {https://gordongeraghty.com/resources/technical-seo/internal-link-depth-modeler},
  note = {Head of Performance, Empire Amplify}
}

Changelog & Version History

  • v1.0.0Initial release of link depth and PageRank flow modeller.