A meta description is a short HTML <meta name="description"> tag that summarizes a page's content. Google often displays it under your title in search results. The recommended length is 150–160 characters (roughly 920 pixels on desktop, 680 on mobile). It is not a direct ranking factor, but it strongly influences click-through rate — and Google rewrites the majority of them anyway.
Think of a meta description the way you think of the blurb on the back of a book. The reader is standing in front of ten covers (the SERP), has 2–3 seconds to pick one, and the blurb is what tips the decision. Your job is to write a blurb so relevant to the searcher's query that Google chooses to show your version instead of generating its own.
Often, no — and this is the single most overlooked fact in older SEO guides. A 2020 Portent study analyzing 30,000 keywords across desktop and mobile found Google rewrote 62.78% of meta descriptions on desktop and 71.43% on mobile. Ahrefs replicated this in 2021 with similar results.
Google rewrites for two main reasons:
The practical takeaway: write your meta description for your primary query, but make sure the rest of your page contains clean, extractable sentences for the long tail. Both your description and your body copy are competing for the snippet slot.
Multiple eye-tracking studies (Nielsen Norman Group, Mediative) show users spend 2–3 seconds scanning a SERP before clicking. Whether the snippet is yours or Google's rewrite, it has to communicate value within that window.
Google truncates by pixel width, not character count. Different surfaces have different cutoffs.
| Surface | Pixel cutoff | Character equivalent | Practical recommendation |
|---|---|---|---|
| Desktop SERP | ~920 px | ~155–160 chars | Aim for 150–160 |
| Mobile SERP | ~680 px | ~120 chars | Front-load the value in the first 120 |
| Open Graph fallback (LinkedIn, Slack) | n/a | ~200 chars before clipping | Set a separate og:description for social |
| Twitter/X card fallback | n/a | ~200 chars before clipping | Set a separate twitter:description |
Even though Google rewrites many of them, the description still pulls weight:
<meta name="description"> when no Open Graph description is present.<head>
<title>Professional Web Design Services | Your Company</title>
<meta name="description" content="Custom, responsive websites that convert visitors into customers. 10+ years experience, fast turnaround, ongoing support — free consultation included.">
</head>Google truncates desktop snippets at roughly 920 pixels (~155–160 characters) and mobile at ~680 pixels (~120 characters). Front-load the most important information.
<!-- Good: 154 chars, specific, scannable -->
<meta name="description" content="Learn 5 proven strategies to double your email open rates in 30 days. Includes templates, examples, and a step-by-step playbook.">
<!-- Too long: ~250 chars, will be truncated mid-sentence -->
<meta name="description" content="This comprehensive guide will teach you everything you need to know about email marketing, including subject lines, templates, segmentation, performance metrics, and much more...">Google bolds query terms in the snippet, which increases CTR. Use the keyword once, in normal-sounding language. Stuffing it three times triggers a rewrite.
<!-- Good: keyword used once, natural -->
<meta name="description" content="Emergency plumber in Chicago — 24/7 drain cleaning, leak repair, and water heater installation. Licensed, insured, locally owned since 1995.">
<!-- Bad: stuffed -->
<meta name="description" content="Chicago plumber plumbing services Chicago emergency plumber drain cleaning Chicago water heater Chicago plumbing company.">Duplicate descriptions are flagged in Google Search Console under "HTML Improvements." They also waste the chance to attract different searcher intents.
The same description on a category page, a product page, and a blog post tells Google none of them is uniquely relevant. Expect rewrites everywhere.
"Welcome to our website" or "Home page of [brand]" offer zero query relevance. Google replaces them with whatever sentence on the page best matches the search.
Repeating the keyword three or more times reads as spam to both users and Google's snippet generator.
Long descriptions are truncated mid-sentence, often cutting off your call to action. They're also the most-rewritten descriptions in the Portent dataset.
If the description promises "free templates" but the page sells a $99 course, Google rewrites it and your bounce rate spikes.
150–160 characters. Google truncates at roughly 920 pixels on desktop and 680 on mobile, which translates to about 155 characters and 120 characters respectively. Front-load the important content in the first 120 characters so it survives mobile truncation.
No. Google publicly confirmed in 2009 that meta descriptions do not influence rankings. They influence click-through rate, which is a behavioral signal but not a direct ranking input.
Most often because your description doesn't match the user's query closely enough, or because it's too long. Portent (2020) measured a 62.78% rewrite rate on desktop and 71.43% on mobile — meaning rewrites are the rule, not the exception.
Every page you want to rank should. For pages you don't want to rank (thin tag pages, internal search results), it's usually fine to leave them off and let Google generate a snippet — or noindex the page entirely.
Indirectly. Generative engines crawl the same HTML and often surface page descriptions in citations. A clean, accurate <meta name="description">helps AI systems summarize your page correctly when there isn't a clearer Open Graph or schema description available.
<meta name="description"> is read by search engines. <meta property="og:description"> is read by social platforms (Facebook, LinkedIn, Slack, iMessage). They can have the same content, but Open Graph allows up to ~200 characters and lets you tailor the social preview separately.
No. Duplicate descriptions are flagged in Google Search Console and weaken every duplicated page's chance of having its description used in the SERP. Each page should have a description tailored to that page's primary query.
A meta description is a 150–160 character pitch for the searcher and a hint for the search engine. Google will rewrite most of yours — but the ones it doesn't rewrite are usually your highest-intent, highest-value queries: branded searches, exact-match titles, and tightly written descriptions that mirror the user's words.
Write each one as if it's the only chance you'll get. For most pages, it is.