Listing tags: 13 tags and 20 characters

What Etsy's help says

From How to Use Tags to Get Found in Search:

• "You can use up to 13 tags per listing."
• "Each tag can contain up to 20 characters."
• A tag can include spaces, letters and numbers. You can use ' and - within words and phrases, but a tag cannot start with them.
• "A single tag can be a short descriptive phrase".
• "To increase your search visibility, use a diverse array of tags."
• Tags "are helpful when there's no matching attribute and are great for aspirational or buyer-minded search terms (for example, "gift for her")".

How to Use Attributes says: "Fill out both attributes and tags for your listings".

Which characters Etsy refuses

Etsy's API reference for creating a draft says valid tags contain only letters, numbers, whitespace, -, ', ™, © and ®. Its pattern names the straight apostrophe and the hyphen. So a curly apostrophe (’) or a long dash (–), which text pasted from a word processor can contain, is not valid.

What to put in them

This is our own suggestion, not Etsy's. Think of what different shoppers would type for this item:

Mistakes we would avoid

Also our own advice:

• Using fewer than 13 when you have more to say.
• Thirteen variations of one phrase. "mountain shirt" and "shirts mountain" add little.
• Repeating your category or an attribute you already filled in. Spend the tag on something new.
• Tags that only repeat the title. Keep those for when you have run out of different phrases.
• Brand or character names: see trademarks.

Good tags describe your listing. Nobody outside Etsy can tell you how a listing will rank, and we do not try.