Substack

Summary: Substack is a newsletter + blog publishing platform with built-in monetization, SEO, and distribution. Official 2024–2025 documentation specifies: 1,800–4,000 word ideal range for technical content; full markdown support including code blocks, callouts, tables, footnotes; 25 MB image limit with auto CDN; canonical URLs, OG/Twitter cards, auto sitemap; paid tiers with 0–100% free preview, referral program, per-post paywalls.

Platform Specifications (2024–2025)

Article Structure & Formatting

  • Headings: # H1, ## H2, ### H3 hierarchy
  • Code blocks: Triple backticks + language for syntax highlighting
  • Callouts: > [!NOTE], > [!TIP], > [!WARNING], > [!IMPORTANT]
  • Tables: Pipe syntax | Header | Header |
  • Footnotes: [^1] with ^[1] Footnote text at bottom
  • Blockquotes: > text for quotes
  • Lists: - or 1. for unordered/ordered

Length & Reading Time

  • Technical audience: 1,800–2,500 words ideal (up to 4,000 for deep dives)
  • General audience: 800–1,500 words
  • Auto reading time: ~200–265 wpm shown at top
  • Email clipping: <3,500 words to avoid Gmail clipping (~102 KB limit includes images)

Images & Media

  • Formats: JPEG, PNG, GIF, SVG, WebP
  • Max size: 25 MB per image
  • Delivery: Auto compression + CDN
  • Alt text: Required for accessibility
  • Galleries: "+ → Gallery" block for multiple images

SEO & Social

  • Meta title: <60 characters
  • Meta description: 150–160 characters
  • Canonical URL: Auto-generated at https://<pub>.substack.com/p/<slug>
  • OG image: 1200×630 px
  • Twitter Card: summary_large_image
  • Sitemap: Auto-generated at https://<pub>.substack.com/sitemap.xml
  • Monitoring: Google Search Console

Monetization

  • Paid tiers: Monthly/annual
  • Free preview: 0–100% per post
  • Referral program: Bonuses for subscriber referrals
  • Stripe tips/donations: Integrated
  • Per-post paywall: Lock individual posts
  • Founder-only posts: Special access for founding members
  • VAT/GST: Handled automatically by Substack

Cross-Posting Strategy

┌─────────────────────────────────────────────────────────┐
│  YOUR DOMAIN (custom domain on Substack)                │
│  e.g., ahans.ai/blog/<slug>  ← rel="canonical" HERE    │
└─────────────────────┬───────────────────────────────────┘
                      │ Cross-post with canonical tag
        ┌─────────────┼─────────────┐
        ▼             ▼             ▼
   ┌─────────┐   ┌──────────┐  ┌─────────┐
   │LinkedIn │   │  X/Twitter│  │Substack │
   │ Article │   │  Thread   │  │ (native)│
   │data-    │   │ 1/N +     │  │ (auto-  │
   │canonical│   │ link to   │  │ canonical│
   │url      │   │ canonical │  │ to your │
   └─────────┘   └──────────┘  │ domain) │
                               └─────────┘
  • Publish on Substack first (canonical source)
  • LinkedIn Article: set data-canonical-url to Substack URL
  • X/Twitter: thread with link to canonical in final tweet
  • No noindex on canonical; cross-posts can have noindex if duplicate concern

Related Entities

  • linkedin — Professional network platform for distribution
  • huggingface — Technical content platform
  • modal — Compute for generating content

Sources

All 8 sources are official Substack Help Center articles or official Substack Blog posts dated 2024–2025. See frontmatter sources array for details.