# How Marketplace Search Ranking Works: A9-Style Factors Explained

URL: https://ecomchannels.com/insights/how-marketplace-search-ranking-works/
Category: AI listings & marketplace SEO
Updated: 2026-10-30

> Marketplace search engines rank listings on relevance and likely conversion. Here are the A9-style ranking factors Australian sellers can actually influence.

Marketplace search engines such as Amazon's (often called A9 or A10) rank products on two broad questions: is this listing relevant to the shopper's search, and is it likely to be bought? Relevance comes from the words and attributes in your listing. Likelihood to convert comes from performance signals such as click-through rate, conversion rate, sales velocity, reviews, price, stock and delivery. You influence both by writing accurate, complete listings and running reliable operations.

## The two-part model behind marketplace search

No marketplace publishes its full algorithm, and "A9" and "A10" are industry nicknames rather than official product names. But the marketplaces do describe the principles. Amazon's own seller guidance says its search system rewards products that are [both relevant to a shopper's query and likely to convert](https://sellercentral.amazon.co.za/welcome/learn/seller-blog/how-to-improve-amazon-listings), and that the guiding principles are relevance, performance and conversion probability (Amazon, 2025).

Think of it as a filter and then a sort:

1. **Filter (relevance).** The engine finds listings whose text and attributes match the query and any filters the shopper applied.
2. **Sort (performance).** Among the relevant listings, it orders them by signals suggesting shoppers will choose and buy that product.

A listing that fails step one never gets the chance to compete on step two. That is why listing data matters before advertising or pricing tactics.

## Relevance factors you control

- **Title.** The strongest relevance field on most marketplaces. Amazon advises placing the primary keyword as early as possible and staying within the 200-character limit for most categories (Amazon, 2025). We go deeper in [product titles that convert](https://ecomchannels.com/insights/marketplace-product-titles-that-convert/).
- **Attributes and item specifics.** These power filters. eBay says buyers filtering results will only see your listing if you have added the matching item specific, and that completing them [improves visibility in search results](https://www.ebay.com/sellercenter/listings/item-specifics) (eBay).
- **Bullets and description.** Secondary keywords and long-tail phrases belong here, written for people first.
- **Backend search terms.** Amazon lets sellers add hidden search terms for synonyms and misspellings, within a 250-byte limit, without repeating words already in visible copy (Amazon, 2025).
- **Category and identifiers.** Wrong categories hide products. Google notes that products with an assigned GTIN submitted without one [may have limited visibility](https://support.google.com/merchants/answer/160161?hl=en) (Google Merchant Center Help), and marketplaces use barcodes to match products to catalogues in the same way.

## Performance factors you influence

Amazon lists these ranking drivers in its seller guidance (Amazon, 2025):

- **Click-through rate**, driven by the main image, a clear title and competitive pricing.
- **Conversion rate** from detail-page sessions.
- **Sales velocity**, meaning consistent demand over time.
- **Review volume and quality.**
- **Availability and fulfilment reliability.** Amazon warns that stockouts can disrupt momentum and hurt rankings for weeks.

Other marketplaces weigh similar signals, plus their own: seller performance metrics, late dispatch rates, cancellation rates and policy compliance. TikTok Shop, for example, tells sellers that the more a title matches buyer search keywords, [the higher the chance the product is seen](https://seller-us.tiktok.com/university/essay?knowledge_id=1664446336747310&lang=en), and it surfaces recommended keywords to help (TikTok Shop, 2026).

## Why page one is not the only goal

Ranking first matters, but shoppers do look further. Salsify's 2025 consumer research found [41% of shoppers will scroll up to page three](https://www.salsify.com/press-release-salsify-2025-consumer-research-report) to find the right product, 26% will go to page five, and only 18% treat it as "page one or bust" (Salsify, 2025). Being indexed for many relevant queries, including long-tail ones, can add up to more traffic than chasing a single head term.

## A practical ranking checklist

1. Put the product type, brand and the most searched differentiator early in the title.
2. Complete every required and recommended attribute in each marketplace's category template.
3. Add correct barcodes and choose the most specific category.
4. Use the main image to win the click and secondary images to answer questions.
5. Keep stock live and dispatch on time; ranking depends on availability.
6. Watch search terms, impressions, clicks and conversion by listing, then fix the weakest step. See [measuring listing performance](https://ecomchannels.com/insights/measuring-listing-performance-ctr-conversion/).

## Key figures

- [41% of shoppers](https://www.salsify.com/press-release-salsify-2025-consumer-research-report) will scroll up to page three of results; only 18% say "page one or bust" (Salsify, 2025).
- eBay Australia says titles of 60 to 80 characters are [2.1 times more likely to sell](https://www.ebay.com.au/sellercentre/private-selling/listing-an-item) (eBay Australia).
- Amazon lists CTR, conversion, sales velocity, reviews and fulfilment reliability among its [key ranking drivers](https://sellercentral.amazon.co.za/welcome/learn/seller-blog/how-to-improve-amazon-listings) (Amazon, 2025).
- Products submitted without an assigned GTIN [may have limited visibility](https://support.google.com/merchants/answer/160161?hl=en) on Google (Google Merchant Center Help).

## How eComChannels helps

Ranking starts with relevance, and relevance starts with complete, rule-compliant data. [eComChannels AI listing optimisation](https://ecomchannels.com/products/ai-listing-optimisation/) drafts titles, bullets, attributes and search terms for each marketplace from one master record, using AI already trained on each channel's listing rules. It flags missing required attributes and barcodes before you publish, so listings are eligible for more searches and filters.

Performance signals depend on operations too. [AI graphics](https://ecomchannels.com/products/ai-graphics/) produces marketplace-compliant image sets that help win the click, and [AI auto shipping](https://ecomchannels.com/products/ai-shipping/) books Australia Post, StarTrack, CouriersPlease and Allied Express consignments and pushes tracking back to each marketplace, supporting the on-time dispatch and valid tracking that marketplaces measure. Fewer manual steps means fewer late shipments and fewer listings slipping in the rankings.

[Book a demo or start a 30-day free trial](https://ecomchannels.com/book-a-demo/) to see how your catalogue scores.

## FAQ

### Is A10 a real Amazon algorithm?

"A9" and "A10" are names widely used by sellers and agencies to describe Amazon's search ranking system. Amazon does not publish its algorithm. Its official guidance focuses on relevance, performance and conversion probability.

### Does advertising improve organic ranking?

Ads can bring extra sessions and sales, and sales velocity is a ranking signal. But ads on a weak listing tend to waste spend. Fix relevance and conversion first.

### How long do listing changes take to affect ranking?

It varies by marketplace and category. Relevance changes can be picked up when a listing is re-indexed, while performance signals build over weeks of sales data.

## Sources
- How to Improve Your Amazon Listings Organically, Amazon Seller Central (Sell on Amazon) (2025): https://sellercentral.amazon.co.za/welcome/learn/seller-blog/how-to-improve-amazon-listings
- Item specifics, eBay Seller Center (2026): https://www.ebay.com/sellercenter/listings/item-specifics
- Optimizing Product Titles, TikTok Shop Seller University (2026): https://seller-us.tiktok.com/university/essay?knowledge_id=1664446336747310&lang=en
- New Survey - 69% of Shoppers Buy While Multitasking (2025 Consumer Research Report), Salsify (2025): https://www.salsify.com/press-release-salsify-2025-consumer-research-report
- About unique product identifiers, Google Merchant Center Help (2026): https://support.google.com/merchants/answer/160161?hl=en
- Listing an Item, eBay Australia Seller Centre (2026): https://www.ebay.com.au/sellercentre/private-selling/listing-an-item