Amazon Buy Box Monitor — Seller, Price & FBA by ASIN

See who holds the Amazon buy box for your ASINs or EANs: the buy box seller, price, shipping, and whether the offer is FBA or Prime, plus every other seller offer on the first page. Run this buy box monitor on a schedule to catch the moment another seller takes over.

It covers 23 Amazon marketplaces and up to 100 ASINs or barcodes per run.

What it does

You give it a list of ASINs, EANs, UPCs or other barcodes and pick a marketplace. For each product the Actor opens Amazon's offer list and returns:

• the buy box offer: seller name and ID, price, shipping, total, condition, FBA, Prime, stock, delivery estimate
• the other offers on the first page of the offer list (about 10), with the same fields and a buy box flag on each
• Amazon's total offer count across all pages, and a flag when the first page does not show them all

ASINs (and ISBN-10s) go straight to the offer list. Barcodes are searched on Amazon first and matched to the first organic search result, so the row also tells you which ASIN that barcode maps to.

Who it is for

• Brand owners and private-label sellers who want to know when a reseller or a hijacker wins the buy box on their listing.
• Resellers who share listings with other sellers and need to see whether they still hold the buy box, and at what price.
• Repricing setups that need the current buy box price and seller as input, per ASIN and marketplace.
• Agencies reporting buy box ownership across amazon.de, amazon.fr, amazon.it and amazon.es for a client's catalogue.

Input

Field	Type	Default	Notes
identifiers	array of strings	(required)	1 to 100 ASINs or barcodes (EAN-8, EAN-13, UPC-12, GTIN-14, ISBN-13, JAN, ISBN-10), mixed freely
marketplace	string	de	de, us, gb (or uk), fr, it, es, nl, be, pl, se, ie, tr, ca, mx, br, jp, in, au, sg, ae, sa, eg, za
zipcode	string	empty	Delivery location. Empty means the capital (10115 Berlin on amazon.de)
includeDetail	boolean	false	Also read the product page (brand, bullet points, images, technical details). Charged separately

Amazon shows prices, shipping and offers for a delivery location, so set zipcode if your customers are mostly in one region. ZIP codes work on de, us, gb/uk, fr, it, es, ca, jp, in, ie and za. The Actor checks the format before it starts. A wrong format, or a ZIP code on another marketplace, ends the run with an input error before any lookup.

Input example

{
  "identifiers": ["B001AXLDDO", "4006381333931"],
  "marketplace": "de",
  "zipcode": "20095"
}

Output

One row per identifier, in input order.

Field	Meaning
query, status	Your value and the outcome: found, not_found, invalid or error
operation	offers-by-asin for ASINs and ISBN-10s, search-by-gtin for barcodes
result.asin	The ASIN checked (for barcodes: the matched ASIN)
result.buy_box	The buy box offer, or null if no offer holds it
result.buy_box.shop_name, .seller_id	Who holds the buy box
result.buy_box.price, .shipping, .total	Buy box price, shipping for the delivery location, and both together
result.buy_box.is_fba, .is_prime	Fulfilled by Amazon, Prime eligible (null when Amazon does not say)
result.offers[]	All page-1 offers; is_buy_box marks the winner
result.offers[].ships_from	Who ships the item
result.offers[].shop_review_rating, .shop_review_count	Seller rating and number of ratings
result.offers_count, result.offers_truncated	Offers across all pages, and whether page 1 shows fewer

Example row (seller names and prices are illustrative):

{
  "query": "B001AXLDDO",
  "operation": "offers-by-asin",
  "country": "de",
  "status": "found",
  "result": {
    "asin": "B001AXLDDO",
    "name": "Träumeland T014301 - Babymatratze Regenbogen 60 x 120 cm",
    "url": "https://www.amazon.de/dp/B001AXLDDO",
    "image": "https://m.media-amazon.com/images/I/41iYiseYxWL.jpg",
    "rating": 4.6,
    "rating_count": 92,
    "buy_box": { "position": 1, "seller_id": "A1EXAMPLESELLER1", "shop_name": "Example Kindermöbel", "condition": "new", "currency": "EUR", "price": 69.95, "shipping": 0, "total": 69.95, "ships_from": "Amazon", "is_fba": true, "is_prime": true, "is_buy_box": true, "stock": 12 },
    "offers_count": 2,
    "offers_truncated": false,
    "offers": [
      { "position": 1, "seller_id": "A1EXAMPLESELLER1", "shop_name": "Example Kindermöbel", "shop_review_rating": 4.7, "shop_review_count": 310, "condition": "new", "currency": "EUR", "price": 69.95, "shipping": 0, "total": 69.95, "ships_from": "Amazon", "is_fba": true, "is_prime": true, "is_buy_box": true, "stock": 12 },
      { "position": 2, "seller_id": "A2EXAMPLESELLER2", "shop_name": "Example Babywelt", "shop_review_rating": 4.2, "shop_review_count": 58, "condition": "new", "currency": "EUR", "price": 64.9, "shipping": 5.9, "total": 70.8, "ships_from": "Example Babywelt", "is_fba": false, "is_prime": false, "is_buy_box": false, "stock": 4 }
    ],
    "detail": null
  }
}

Offers also carry shop_url (the seller's page), condition_text, list_price, shipping_note, availability_text, delivery_min_hours and delivery_max_hours. Free shipping on Amazon is often conditional, so shipping_note keeps Amazon's own wording. stock is how many units Amazon lets a buyer add to the cart, which can be capped below the seller's real stock.

Scheduling

Each run is one snapshot. The Actor does not keep a history or compare runs on its own. To monitor the buy box:

1. Save your input as a task (one task per marketplace works well).
2. Add an Apify schedule for the task, for example every few hours.
3. Compare result.buy_box.seller_id and result.buy_box.total per ASIN between the latest dataset and the one before, in your own system or with an integration that runs after each run.

Keep the task input the same between runs so the rows line up. Stagger schedules for different tasks: up to 100 Amazon lookups from this Actor can be in progress for your account at once, and runs that start together compete for that capacity.

Billing

Pay per event. See the Pricing tab for current rates.

• ean-lookup: charged once for every found or not_found row, whether you gave an ASIN or a barcode.
• detail: charged once for every found row that includes product page data. It is off by default here; leave it off unless you need it.
• invalid and error rows are free.

Rows are written before anything is charged. If a run reaches your maximum cost per run, you still get all rows and only the part within budget is charged.

Statuses and errors

status	Meaning	Charged
found	Offer list read. A listing with no sellers right now is found with offers: [] and buy_box: null	yes
not_found	The ASIN does not exist on this marketplace, or a barcode had no organic search result	yes
invalid	Not a valid ASIN or barcode. Nothing was looked up	no
error	Lookup failed; see errorCode	no

errorCode	statusCode	Meaning
invalid_input	400	Why an invalid value was rejected
free_limit_reached	402	The free plan's result allowance does not cover this value
timeout	408	No answer before the run's deadline
concurrency_limit_reached	429	Your other runs held all lookup capacity, and the waits (15 to 240 seconds) ran out
internal_error	500	Amazon could not be fetched for this value right now

Each run has an 890-second lookup budget; anything unfinished becomes a free timeout row. Set the run or task timeout to at least 960 seconds. The run always ends as Succeeded, so check each row's status rather than the run status.

FAQ

Does it alert me when the buy box changes? Not by itself. It returns the current buy box on every run. Compare runs on your side, as described under Scheduling.

Why is buy_box null when there are offers? None of the offers on page 1 carries Amazon's buy box marker, so there is no winner to report. Amazon does not award a buy box on every listing.

Should I use ASINs or EANs? ASINs, if you have them. They skip the search step, so you always get the exact listing you asked for. With a barcode, the Actor uses Amazon's first organic search result, which is usually but not always the right product.

Are all sellers included? The offers on the first page of Amazon's offer list are included, usually about 10. offers_count tells you how many there are in total, and offers_truncated is true when some are missing from offers.

Questions or higher limits: support@anyprice.dev