Meta descriptions explained: SEO impact & how we check them

What is a meta description?

A meta description is an HTML element placed in a page's <head> section:

<meta name="description" content="A concise, accurate summary of this page's content, written for the searcher.">

Google builds most snippets from the page's own text. It uses the meta description when it judges it a more accurate summary for that query. So the tag is a request, not a guarantee. It's still the only part of the snippet you write directly.

Why it matters for SEO

• It's the pitch, not a ranking input. Google's snippet documentation treats the description as a snippet source. It doesn't describe it as a ranking signal. What it affects is whether someone who sees your result chooses to click it.
• Missing or generic means Google writes it for you. Without a usable description, the snippet is whatever text Google picks from the page, which may not be the part you would lead with.
• Identical descriptions don't help. Google's documentation says identical or similar descriptions on every page of a site aren't helpful when individual pages appear in results.

How our engine checks meta descriptions

These are the rules as implemented in our engine, not a paraphrase of best practice. Two things apply to all three checks:

• We read the HTML as served, before JavaScript runs. A description injected by a script after load (some single-page apps and tag managers do this) is invisible to us, and possibly to crawlers that don't render.
• We use the first non-empty one. We take the first <meta name="description"> whose content isn't blank. The attribute name is case-insensitive, HTML entities are decoded (& counts as one character) and surrounding spaces are trimmed. If a theme and an SEO plugin both print one, we use whichever comes first. That may not be the one you edited.

Check 1: onpage-meta-description-missing

Severity: Warning · Runs in: free audit and full crawl
Fails when: there is no description tag, or every description tag's content is empty or only spaces. content="" counts as missing.

Check 2: onpage-meta-description-too-long

Severity: Warning · Runs in: free audit and full crawl
Fails when: the description is longer than 160 characters. Exactly 160 passes. There is no minimum, so a 12-character description passes this check, even though it won't earn a click.

Characters are counted the way JavaScript counts string length. Most emoji count as 2, so a 159-character description ending in 🚀 fails. Spaces inside the text are counted as written.

Check 3: onpage-meta-description-duplicate

Severity: Warning · Runs in: full crawl only
Fails when: two or more crawled pages share the same description, ignoring case and collapsing runs of spaces. Every page in the group fails. The free audit sees a single page, so it can't detect duplicates and the check doesn't appear in a free report.

Reproduce what our checker saw

If your report disagrees with what you see in your CMS, run this in the browser console on the page in question. It fetches the page's HTML as served and applies the same rules as checks 1 and 2:

const html = await (await fetch(location.href)).text();
const doc = new DOMParser().parseFromString(html, 'text/html');
const d = [...doc.querySelectorAll('meta')]
  .filter(m => (m.getAttribute('name') ?? '').trim().toLowerCase() === 'description')
  .map(m => (m.getAttribute('content') ?? '').trim())
  .find(Boolean) ?? null;
console.log(d === null ? 'MISSING'
  : `${d.length} chars: ${d.length > 160 ? 'TOO LONG' : 'ok'}`, d);

If it prints MISSING but your CMS shows a description, the tag is probably added by JavaScript, or the page is served from a cache that predates your edit. If the text isn't the one you wrote, a second tag earlier in the <head> is winning. View the source and search for name="description" to find it.

How to read your result

• Pass: a non-empty description of 160 characters or fewer was found. This says nothing about whether it's good. Read it as a searcher would.
• Warning: missing. No usable description in the served HTML. Write one, or find out why your CMS isn't printing it.
• Warning: too long. Over 160 characters. Put the point in the first 120 characters and trim the rest.
• Warning: duplicate (full crawl only). Other pages share this text. It's usually a template default. Write one for each page that matters.

How to fix missing or duplicate meta descriptions

Where to set the description on each platform:

• WordPress →
• Shopify →
• Webflow →
• Wix →
• Squarespace →

To see how a draft reads before publishing, type it into our SERP preview. To inspect a live URL's tags, use the meta tag analyzer. Titles follow similar rules. See title tags explained.

FAQ