My description fits in the desktop preview but gets cut in the mobile one. Why, and which should I go by?
Because phone screens are narrower, the width at which descriptions are commonly seen in full is smaller on mobile than on desktop. The tool compares your description's width with roughly 920 px for desktop and roughly 680 px for mobile; these are commonly observed widths, not limits search engines publish. Since many shoppers search on phones, make your first sentence complete on its own and put the details after it.
One measurement, two comparisons
In the Search snippet preview, the description's width is measured once, in Arial at 14 px, and then compared with two different guides. Suppose your browser measured your description at about 750 px:
- Desktop: 750 is below 920, so the status is within.
- Mobile: 750 is above 680, so the status is wider and may be cut.
That is why you see two different messages for the same description. At about 650 px it would be within both. The preview cards themselves show at most two lines of description on the desktop card and at most three lines on the narrower mobile card, so you may see the cut with your own eyes as well.
Which to go by
You do not have to choose. The practical approach is a description that works in both: its first part, within what shows on mobile, carries the whole message, and what follows is a bonus for people who see it in full on desktop. That way nobody loses anything important if it is cut.
Do not treat either figure as an exact limit. Engines use their own fonts and layouts, may change them, and may rewrite the description entirely or pick text from your page that fits the search.
Ordering a description for a phone screen
- Open with what the customer searches for and what sets you apart, in a short sentence: Original Cambodian oud oil in several strengths.
- Follow with your strongest reason to buy from you, such as delivery or returns, if it is true.
- Put less important details last: extra sizes, gift wrapping.
- Watch the mobile status in the tool. If it says wider, read the description and ask: if it stopped about here, would the point get across?
- Do not cut everything just to reach within: a very short description may not say enough, and desktop shows more.
The title is different
The tool does not give a separate mobile guide for the title, only one desktop title guide of roughly 580 px. On the mobile card the title wraps onto more lines instead of being cut on one. That is why this question is about the description. If you want to count a description's words and characters as read while drafting it in a document, paste it into the Word and character counter; the pixel width, though, only comes from the preview.
Common questions
Why does the tool not give me a character limit for mobile?
Because cutting depends on width, not count. As a rough guide only, about 680 px corresponds to roughly 120 Latin characters, and it differs for Arabic.
Does a long description hurt my ranking?
No. Description length is not a ranking factor in itself, and nothing in the tool affects ranking. It is about how clear the result is to the searcher.