How to Write an SEO Meta Description

The meta description is the short text that shows up under the title in a search result. It doesn't directly affect ranking, but it noticeably changes click-through rate.

Summary

The meta description is the short text that shows up under the title in a search result. It doesn't directly affect ranking, but it noticeably changes click-through rate.

Step by step

Keep it around 150-160 characters. Anything longer gets cut off by Google.
Instead of repeating every word from the page, say clearly what someone will find if they click through.
Work the target keyword into a natural sentence. Forcing it in awkwardly tends to lower click-through rate.
Write a unique description for every page. Reusing the same one across pages can lead Google to just generate its own summary instead.

Why it matters

On a results page, people decide what to click in a few seconds. The title gets their attention. The description answers the question 'is what I need actually here?'. When two pages sit at similar positions, the one with the clearer description tends to win the click. More clicks from the same ranking means more visitors without moving up a single spot. A good description also filters out people who would have arrived with the wrong expectation and left immediately.

Google won't always show yours

A meta description is a suggestion, not a guarantee. Google may pick other text from the page when it thinks that fits the query better. This usually happens when your description doesn't match the content, is too vague, or doesn't touch on what the person searched for. You can't fully prevent rewrites, but a description that states the page's main point plainly gives yours a better chance of being used.

Common mistakes

Copying the page's first paragraph. Intros often warm up to the topic, while a search snippet needs to state the benefit right away.
Putting the key information at the end. Snippets can be cut shorter on mobile, so the main point belongs in the first sentence.
Using double quotation marks. Some systems cut the description off at the first double quote; single quotes are safer.
Promising something the page doesn't deliver. Writing 'free download' and sending people to a signup form may get clicks once, but it costs trust.
Reusing one template across hundreds of product or category pages with only the product name swapped.

A realistic scenario

A PDF compression tool's page had this description: 'PDF compressor, PDF reducer, shrink PDF size tool.' The keywords are there, but it says nothing about what the visitor gets. The rewrite: 'Shrink a PDF that's too big to email, without signing up, and keep the text and images readable.' Both target the same search, but the second names the actual problem, which is a file that won't fit in an email.

How to measure the effect

Before you change a description, note the page's impressions and click-through rate in Search Console. Wait a few weeks after the change, then compare periods of the same length. If the position held steady and the click-through rate went up, the new description is doing its job. Start with a few high-traffic pages instead of rewriting everything at once. It makes it much easier to see what worked.