SEO Preview
Every page on your dev server has a companion preview at /{slug}/seo-preview. It shows exactly what search engines, social platforms, and messaging apps will display when someone shares or finds your page. The homepage preview lives at /seo-preview.
Keyboard Shortcut
Press ⌘. (Mac) or Ctrl+. (Windows/Linux) to open the current page's SEO preview in a new browser tab. This works on any page while the dev server is running.
What's Included
The preview page has seven sections:
| Section | What it shows |
|---|---|
| Search | Google-style SERP entry with URL breadcrumb, title, and description |
| Social | Open Graph card as it appears on Facebook, LinkedIn, Twitter/X |
| Mobile | Link bubble preview as seen in iMessage, WhatsApp, Slack |
| Browser | Tab bar mockup with favicon and truncated title |
| Keywords | Top 15 keywords extracted from your page content with frequency counts |
| Meta | Full audit table of every meta tag with character count badges |
| Data | JSON-LD structured data that would be embedded in the page |
Character Count Badges
Every text field that search engines or social platforms truncate shows a colored badge:
- Green — within recommended limit
- Yellow — approaching the limit (over 85%)
- Red — over the limit, will be truncated
Recommended limits:
| Field | Limit |
|---|---|
| Page title | 60 characters |
| Meta description | 155 characters |
| OG title | 60 characters |
| OG description | 155 characters |
| Twitter title | 70 characters |
| Twitter description | 200 characters |
| Browser tab title | 30 characters |
How It Works
SEO preview pages are generated during every build, alongside your regular pages. They use the same layout and theme as your site — nav, footer, and theme toggle all work normally.
The preview resolves SEO data using the same logic as activated builds — title suffix, description derivation, canonical URLs, OG image paths, and schema type detection. The preview works identically whether your site is trial or activated.
Title Suffix
Every page gets a titleSuffix field auto-populated in its frontmatter (e.g. " | sitemd"). This suffix is appended to the page title in the browser tab, Google results, and social cards. The default comes from your brandName in settings/meta.md.
To customize a specific page's suffix, edit titleSuffix directly in that page's frontmatter. To remove the suffix entirely for a page, set titleSuffix: none. The homepage always uses just the site title — no suffix is added.
OG Images in Preview
When ogImage: auto is set in settings/seo.md (the default), the dev server generates a single branded OG card on startup and after every file change rebuild. The card uses your theme colors (based on defaultMode in theme.md) and brand identity — all pages share the same image. The social and mobile card previews load this image directly, so you see exactly what will appear when someone shares your page.
To use a custom image for a specific page, add image: /path/to/image.png to that page's frontmatter. The preview picks it up immediately — that page will use your custom image instead of the shared brand card.
Before activation
If your site has not been activated yet, OG images cannot be generated. The preview shows an informational placeholder. Authenticate and run sitemd activate to enable OG image generation.
Never Deployed
Preview pages exist only on the dev server. They are:
- Excluded from
sitemap.xml - Excluded from the search index
- Excluded from
llms.txtandllms-full.txt - Not written to disk during production builds
- Tagged with
<meta name="robots" content="noindex">
Related
- SEO — full SEO configuration reference
- Build Modes — trial vs activated
- Live Build Sync — how the dev server watches for changes