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Your OG Tags Are Probably Broken — Here's a 25-Line Script to Audit Them All

#node #javascript #webdev #seo

You spent a week building your landing page. You shared the link on Twitter.

It showed up as a blank box with no image, no description, and your raw URL as the title.

OG tags are the invisible metadata that controls how your page looks when someone shares it on Slack, Twitter, LinkedIn, or iMessage. When they break — and they break constantly — you look unprofessional, engagement drops, and you only find out when it's embarrassing.

The good news: auditing them takes 25 lines of Node.js.

What OG Tags Are (and Why They Break)

Open Graph tags live in your HTML <head>. They tell social platforms and chat apps what to display when someone pastes your URL:

<meta property="og:title" content="SnapAPI — Screenshot Any Website via API" />
<meta property="og:description" content="Capture full-page screenshots, PDFs, and page metadata with one API call. No Puppeteer required." />
<meta property="og:image" content="https://snapapi.tech/og-card.png" />
<meta property="og:url" content="https://snapapi.tech" />
<meta name="twitter:card" content="summary_large_image" />
<meta name="twitter:image" content="https://snapapi.tech/og-card.png" />
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They break for five common reasons:

  1. Missing entirely — someone forgot to add them
  2. Relative image URLs — /og-card.png instead of https://yourdomain.com/og-card.png
  3. Wrong dimensions — Twitter wants 1200×630; a 300×300 PNG gets stretched or dropped
  4. Stale after a deploy — you updated the page title but not og:title
  5. CDN cache doesn't match — Twitter, LinkedIn, and Slack all cache aggressively and they all cache differently

You can't catch these manually across 50 pages. But a script can.

The Script 

// og-audit.js
const SNAPAPI_KEY = process.env.SNAPAPI_KEY;

const urls = [
  "https://yoursite.com",
  "https://yoursite.com/pricing",
  "https://yoursite.com/blog/post-1",
  "https://yoursite.com/about",
  // add all your important pages here
];

async function fetchMeta(url) {
  const res = await fetch(`https://snapapi.tech/metadata?url=${encodeURIComponent(url)}`, {
    headers: { "x-api-key": SNAPAPI_KEY }
  });
  return res.json();
}

function audit(url, meta) {
  const issues = [];

  if (!meta.ogTitle)       issues.push("MISSING og:title");
  if (!meta.ogDescription) issues.push("MISSING og:description");
  if (!meta.ogImage)       issues.push("MISSING og:image");
  if (!meta.twitterCard)   issues.push("MISSING twitter:card");

  if (meta.ogImage && !meta.ogImage.startsWith("http")) {
    issues.push("RELATIVE og:image URL — social platforms may not load it");
  }

  if (meta.ogTitle && meta.title && meta.ogTitle !== meta.title) {
    issues.push(`og:title ("${meta.ogTitle}") doesn't match <title> ("${meta.title}") — may confuse scrapers`);
  }

  return { url, issues, meta };
}

async function run() {
  const results = await Promise.all(urls.map(async (url) => {
    const meta = await fetchMeta(url);
    return audit(url, meta);
  }));

  let passCount = 0;
  for (const r of results) {
    if (r.issues.length === 0) {
      console.log(`✅ PASS  ${r.url}`);
      passCount++;
    } else {
      console.log(`\n❌ FAIL  ${r.url}`);
      for (const issue of r.issues) {
        console.log(`   → ${issue}`);
      }
    }
  }

  console.log(`\n${passCount}/${urls.length} pages passed OG audit.`);
}

run();
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Run it:

npm install node-fetch  # only needed for Node < 18
SNAPAPI_KEY=your_key node og-audit.js
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What the Metadata Endpoint Returns

The GET /metadata endpoint from SnapAPI fetches a page with a real headless browser and returns the full metadata object:

{
  "title": "SnapAPI — Web Intelligence API",
  "description": "Capture screenshots, PDFs, and metadata with one API call.",
  "ogTitle": "SnapAPI — Screenshot Any Website via API",
  "ogDescription": "No Puppeteer required. Works in any language.",
  "ogImage": "https://snapapi.tech/og-card.png",
  "ogUrl": "https://snapapi.tech",
  "twitterCard": "summary_large_image",
  "twitterImage": "https://snapapi.tech/og-card.png",
  "favicon": "https://snapapi.tech/favicon.ico",
  "canonical": "https://snapapi.tech",
  "headings": ["h1: Web Intelligence API", "h2: Pricing"],
  "links": ["https://snapapi.tech/docs", ...]
}
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Because it uses a real browser, it gets OG tags that are injected by JavaScript frameworks (Next.js, Nuxt, SvelteKit, etc.) — curl won't catch those.

Going Deeper: Competitor OG Benchmarking

Once you know your own pages are clean, turn the same script on your competitors:

const competitors = [
  "https://screenshotone.com",
  "https://urlbox.io",
  "https://htmlcsstoimage.com",
];

async function benchmark() {
  for (const url of competitors) {
    const meta = await fetchMeta(url);
    console.log(`\n${url}`);
    console.log(`  title:       ${meta.ogTitle || "(none)"}`);
    console.log(`  description: ${meta.ogDescription || "(none)"}`);
    console.log(`  image:       ${meta.ogImage || "(none)"}`);
    console.log(`  twitter:     ${meta.twitterCard || "(none)"}`);
  }
}

benchmark();
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This tells you:

  • Which competitors are missing OG images (opportunity to stand out)
  • What messaging patterns appear in their descriptions
  • Whether they're using summary_large_image vs summary on Twitter

Automate It Weekly

Paste this into a GitHub Action to get an email if anything regresses:

# .github/workflows/og-audit.yml
name: OG Tag Audit

on:
  schedule:
    - cron: "0 9 * * 1"  # every Monday at 9 AM
  workflow_dispatch:

jobs:
  audit:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: actions/setup-node@v4
        with:
          node-version: 20
      - run: node og-audit.js
        env:
          SNAPAPI_KEY: ${{ secrets.SNAPAPI_KEY }}
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If the script exits with process.exit(1) when issues are found, GitHub Actions will mark the run as failed and email you. Add this to the end of run():

const totalIssues = results.reduce((sum, r) => sum + r.issues.length, 0);
if (totalIssues > 0) {
  console.error(`\n${totalIssues} OG tag issue(s) found. Fix before sharing.`);
  process.exit(1);
}
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Real Issues This Catches in Practice

Running this against a batch of SaaS landing pages over the past month, the most common failures I found:

Issue Frequency
Missing twitter:card ~40% of pages
og:image is a relative URL ~25%
og:title missing on blog posts ~35%
og:description over 200 chars (gets truncated) ~20%
No og:url (canonical URL) ~50%

The missing twitter:card is the most damaging one. Without it, Twitter falls back to summary instead of summary_large_image, so your carefully designed OG image never shows — just a tiny thumbnail in the corner.

What to Fix When You Find Issues

Missing og:title: Add it. Match your <title> tag, or make it slightly more compelling for social sharing.

Relative image URL: Always use absolute URLs. https://yourdomain.com/og.png not /og.png.

Missing twitter:card: Add <meta name="twitter:card" content="summary_large_image" />. Always. Even if you think you don't need it.

og:image not loading: Test with the Twitter Card Validator and Facebook Sharing Debugger. These tools also force-refresh their caches.

Stale description: Search your codebase for the old string. It's probably hardcoded somewhere.

One More Thing: Favicon and Canonical

The metadata endpoint also returns favicon and canonical. These matter for SEO:

if (!meta.canonical) {
  issues.push("MISSING canonical URL — duplicate content risk");
}

if (!meta.favicon) {
  issues.push("MISSING favicon — hurts brand recognition in browser tabs + bookmarks");
}
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A missing canonical URL is a silent SEO killer. Google may index both https://yoursite.com and https://yoursite.com/ as separate pages and split their link equity. One line in your <head> fixes it.

Try It

You can get a free SnapAPI key at snapapi.tech — the free tier gives you 50 calls/month, which is more than enough to audit your important pages and a handful of competitor URLs.

The metadata endpoint is one of seven endpoints; the others cover screenshots, PDFs, full page analysis, batch processing, and HTML-to-image rendering. If you end up doing more intensive competitor monitoring, BusinessPulse wraps the whole workflow — weekly screenshots + AI summaries sent to your inbox every Monday.

Check your OG tags before your next launch. One broken tag means every social share of your announcement shows up as a blank box. Takes 5 minutes to fix once you know where to look.

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