Baron Munchausen’s Crawl Test Lab

Meta Description Length: Too Long and Too Short Examples

My hearer could listen to the grass grow, and even he could not tell when I had finished describing the Moon.

The short answer

What it is
Meta description length is the size of a page's description, measured in characters and in pixels. A description can be too short to help, or too long to show in full.
Why it matters
Search results cut off long descriptions, so the end of your message can be lost. A very short description wastes space that could give people a reason to click.
How a crawler should report it
Report a meta issue when the length is under 70 or over 160 characters. Flag desktop truncation when the width in Arial at 14 px is over 920 px, and mobile truncation when it wraps to more than 3 lines at 343 px.
Live examples
A horse drinking at a fountain while the water pours out of its missing back half.
Fig. 75. It pours in at one end and runs off the other.

Fitting a page summary into the space under a search result

Meta description length has no official limit in HTML or in Google's documentation. Search results do have limited room, though, so long text gets cut off with an ellipsis. Short descriptions tend to come from quick edits, such as a single phrase in a CMS field. Long ones often come from a first paragraph that was pasted in or added by a plugin. Both can occur on the same site.

The space you get is measured in pixels, and it changes with the device. A description of narrow letters fits in more characters than one of wide letters. On a phone, the text wraps in a narrow column and stops after a few lines. Google also changes the snippet to suit the search. It may show your tag, part of it, or some other text from the page. A good length improves your odds, but it is no promise.

A crawler can check three things. Count characters, and flag anything under 70 or over 160. Measure the width in Arial at 14 pixels, and flag text over 920 pixels for desktop. Then wrap the text at a width of 343 pixels and flag anything over 3 lines for mobile. A description of exactly 160 characters is within the rule. Pay attention to edge cases, as a one-off error here is easy to make.

To fix a long description, put the key message and the search phrase in the first half, so that a cut does no harm. Remove filler, such as "Welcome to our website". To fix a short description, add a concrete detail, like what the reader will learn or get. Aim for one or two plain sentences. End on a full thought. Review your most-visited pages first, because those are the ones that gain the most.