Price Comparison Methodology
Last updated: May 27, 2026
This page explains exactly how Cheapzix finds, ranks, and displays prices — including our data sources, freshness guarantees, ranking logic, and the limitations you should know about.
Data sources
Every Cheapzix search queries two sources in parallel:
1. Amazon product index
We query Amazon product listings directly using the SearchAPI.io Amazon search integration. This returns prices, condition (new/used/renewed), seller details, and Prime eligibility. We automatically localize the Amazon domain by visitor country — shoppers in Canada see Amazon.ca prices, UK visitors see Amazon.co.uk, and so on.
2. Google Shopping index
We query the Google Shopping product index, which aggregates listings from Walmart, Best Buy, Target, eBay, Costco, Home Depot, Sephora, REI, and other retailers. Results from Google Shopping are returned as organic listings, not sponsored placements — we exclude ads from our result set.
Why both? Google Shopping typically omits or deprioritizes Amazon results. Running both searches fills that gap, so you see the full market — not just what retailers paid to promote.
Price freshness
| Situation | What you see |
|---|---|
| First search for a query | Retailer results fetched when you search — typically under 2 seconds |
| Same query within 20 minutes | Cached prices (identical to the live fetch, served faster) |
| Blog/price-guide pages | Retailer listings compared when available via the Cheapzix API — always verify on the retailer site |
| Price history widget | Historical low/high based on our 7-day rolling price log for recently searched queries |
Prices are accurate at the moment of fetch. Retailers can change prices between the time we fetch and the time you click through, so always confirm the price on the retailer's site before purchasing.
Ranking and sorting
Results are sorted by price, lowest first, by default. There are no sponsored positions. Retailers with affiliate agreements are not ranked higher than retailers without them. The sort is purely numeric — the cheapest listing for a given product appears first.
Secondary filters (condition, store, sort by trust score) are applied by the user, not by us. Our "trust score" is a transparency signal that penalizes listings without verifiable seller ratings, not a ranking boost for paying retailers.
What we exclude
- eBay search pages: We exclude eBay listing-search URLs (ebay.com/sch/). We only include direct eBay product listing pages (ebay.com/itm/), which represent a specific item rather than a search result page.
- Listings without prices: Results with a $0 or missing price are filtered out before display.
- Sponsored Google Shopping ads: We use organic Shopping results only.
- Non-US retailers (for US visitors): International listings without US shipping are excluded from US-localized results.
Affiliate links
Some outbound links carry affiliate tracking codes. These are:
- Amazon links include the Associates tag
cheapzix-20 - eBay links include the EPN campaign ID
- Some other retailers via CJ Affiliate
Affiliate relationships do not affect ranking, inclusion, or presentation of results. A non-affiliate retailer that has the lowest price will appear first. See our Affiliate Disclosure for the full FTC compliance statement.
Price guides (blog pages)
Our static price guide pages (e.g., iPhone 16 price comparison) embed the same live-price widget as the main search. When you load a price guide, it calls the Cheapzix API for the specific product and displays current prices from retailers. The editorial content on those pages (buying tips, FAQ, model comparisons) is written and reviewed by the Cheapzix editorial team.
Limitations
- Not every retailer: We search Amazon and Google Shopping. Retailers that don't list on either platform (e.g., niche direct-to-consumer brands) won't appear in results.
- In-store prices: We compare online prices only. In-store pricing, local promotions, and membership discounts (e.g., Costco membership pricing) may differ.
- Shipping and taxes: Prices shown are pre-shipping and pre-tax unless the retailer includes them in the listed price. Final checkout costs may be higher.
- Used / renewed items: Condition labels ("Renewed", "Used – Good", etc.) come from the retailer. We don't independently verify seller claims.
Questions about our methodology
If you spot a pricing discrepancy, a missing retailer, or a result that looks wrong, we want to know. Contact us with the product name and what you observed.