A meta description is the short summary you set in the <meta name="description"> HTML tag. Search engines may use it as the snippet shown beneath your title in the search results, and social platforms read the same tag (or its OpenGraph equivalent) when rendering link cards.
What Google actually does with it
- Uses it as the snippet: roughly 30% of the time, mostly on transactional and brand-specific queries.
- Rewrites it: the other ~70%. When a passage on your page better matches the user's query, Google pulls that passage instead — your meta is ignored.
- Truncates it: roughly 920 pixels of width on desktop, ~680px on mobile. In practice 130-160 characters depending on letter widths.
Why it still matters
Even though Google rewrites most of them, the meta you write is still used:
- On social platforms (LinkedIn, X, Facebook) verbatim
- By voice assistants and AI Overview tools as a signal of page intent
- By Google ~30% of the time, particularly for branded or transactional queries
A well-written meta correlates with higher click-through rate even on the SERPs where Google rewrites it, because page-level signals improve overall.
Common mistakes
- Stuffing the keyword — Google explicitly discourages this; reads as low-quality.
- Generic brand boilerplate — "Welcome to Acme, where we…" gets rewritten 100% of the time.
- Exceeding 160 characters — truncates with an ellipsis. Use a pixel-aware tool to check the real cutoff.
For the practical pre-publish workflow, see our blog post on how long a meta description should be.