Amazon Backend Search Terms: What to Put In, What to Leave Out

Every listing has a field shoppers never see: the search terms, often called backend keywords. It exists to catch the ways people search that your title and bullets do not cover. Many sellers either ignore it or stuff it with every word they can think of, and both habits waste it. Used well, it is a short, clean list of synonyms and variants, written once and audited a few times a year. This guide explains what the field does, what belongs in it, what to keep out, why the limit is measured in bytes, and a routine for keeping it in good shape.

What the field is for

When Amazon decides which searches a product could match, it reads your title, bullets, description, product attributes and the search terms field. The field is the place for words that are true of the product but would make your visible copy awkward: other names for the same thing, abbreviations, alternate spellings and terms in a second language that your customers use.

Amazon has not published how it weighs hidden terms against visible text, so do not treat the field as a ranking lever. Treat it as coverage. If a shopper searches for a word that appears nowhere in your listing, you have given Amazon no reason to show you. The field closes that gap cheaply, without bending your sentences around keywords.

What belongs in it

Start from evidence, not imagination. The best candidates are words shoppers already use that your visible copy lacks.

• Synonyms and alternate names, such as 'tee shirt' for a 't-shirt' or 'sneakers' for a 'tennis shoe'.
• Abbreviations and the spelled-out form of the same thing, when shoppers use both.
• Variants that are genuinely different forms of a word, such as a hyphenated and a joined version, or a two-word and a one-word compound.
• Spanish terms for the US market, where Spanish-language searches are a real part of your category. Use correct Spanish, with the accents it needs.
• Uses, audiences or occasions that are true of the product but absent from your copy, such as 'camping' for a compact stove.

Where do those words come from? Four places are worth checking. The customer search term report from your Sponsored Products campaigns shows terms that bring orders but appear nowhere in your listing text. Search Query Performance in Brand Analytics, if you are enrolled in Brand Registry, shows what shoppers type before they reach your category. The words customers use in reviews and questions show how real buyers describe the product. And the suggestions that appear as you type in Amazon's search bar show phrases people actually search.

Keep only terms that are accurate for the product. A shopper who lands on the wrong item costs you a click, and often a return as well. On format, Amazon's guidance has been to separate terms with spaces rather than commas and that order does not matter, so a word that would appear in three of your phrases needs to appear only once. Search also tends to handle capital letters and plurals, so a long run of near-identical forms spends room that new words could use. Read the field's current help text, because these details change.

What to leave out

• Other brands' names, including competitors. Amazon's keyword guidelines prohibit them, and they invite trademark complaints. Check the current policy before using a brand name even to describe compatibility.
• Words already in your title, bullets or attributes. Repeating them adds length and nothing else.
• Subjective or promotional words such as 'best', 'cheapest' or 'top rated', and time-limited words such as 'new' or 'sale'.
• Claims you cannot support, especially health and safety claims, and any word for a feature the product does not have.
• Punctuation, symbols and filler words such as articles and prepositions, which Amazon has said are unnecessary.
• Words for a different kind of product that shoppers might also buy. A term that attracts the wrong shopper adds clicks and lowers your conversion rate.
• Your own brand name, which is already tied to the listing through its brand attribute.

These are not style preferences. The field falls under the same policies as the rest of the listing, and misleading or prohibited terms can lead to the terms being removed or the listing being flagged. Keep it as clean as visible copy.

Why the limit counts bytes, not characters

Seller Central gives a limit for this field and measures it in bytes. Do not rely on a figure you read in an article, this one included: open the field's help text and check the current number and how it is counted. What matters here is the difference between a byte and a character.

Text on the web is usually stored in a format where each plain English letter, digit and space takes one byte, and a letter with an accent, such as é or ñ, takes two. An all-English list therefore uses about one byte per character, while a Spanish list uses more. The word 'niños' has five characters and six bytes. 'Sartén' has six characters and seven bytes. A list with many accented words can run past the limit while a character counter tells you that you are comfortably inside it.

Going over is not a small mistake. Amazon's guidance indicates that terms beyond the limit may not be indexed, and depending on the template a field that is too long can be ignored or rejected as a whole. Finish with a margin under the limit, and use a counter that reports UTF-8 bytes rather than characters.

When space is tight, rank your candidate words by evidence rather than by gut feel. Words that already bring orders in your ad reports come first. Next come words that shoppers clearly use but that you have not tested. Last are words that are merely possible. Cut from the bottom of that list. If you sell in more than one language, give the second language its own short list so you can see how much of the limit it takes, and decide on purpose whether it earns that share.

A quarterly audit routine

Fill the field carefully once, then audit it at a fixed interval, say every quarter, and after any change to the title or main bullets. A routine stops the list drifting out of date or filling up with leftovers.

The brand-name search in the checklist is only a hint. If the listing appears for the term plus your brand, that term is probably being read. If it does not, treat that as a reason to look closer, not as proof, because search results depend on many things besides the field. Judge the work by what happens afterwards: new search terms in your reports, and orders that arrive through words you added.

The short version

• Use the field for words that are true of the product but missing from your visible copy.
• Source them from search term reports, Brand Analytics, reviews and Amazon's suggestions.
• Leave out other brands, repeats, subjective claims, time-limited words and punctuation.
• Check the current byte limit in Seller Central and stay safely under it, especially with accented words.
• Audit the field every quarter and after any title change.