Amazon Listing Monitoring

Real-time monitoring for every listing you own, down to the fields Amazon changes without telling you.

Know what changed, why it changed, and whether it's costing you.

Your Buy Box lost to a competitor. A hijacker on your listing. Amazon changing your description. A listing search suppressed, with Amazon's reason. A fee that quietly went up. SentryKit catches it in real time and tells you which changes are actually costing you money.

• Buy Box (Featured Offer) Lost / Won • Hijacker Detected • Listing Suppressed, with Amazon's reason • Backend Field Change • Main Image Change • Account Health Drop • FBA Fee Change
Start free trial →

14 days free, no card. Then $19/mo  ·  unlimited ASINs  ·  every marketplace  ·  See pricing →

🇬🇧 🇩🇪 🇫🇷 🇮🇹 🇪🇸  Prices in your marketplace's currency, across 22 Amazon marketplaces.

Real-time alerts 50+ signals per listing Unlimited ASINs No commitments
SentryKit dashboard
What sellers tell us

Fast alerts, clear detail, and a team that listens.

“The notification arrived even before I saw it in Seller Central, so perfect!”
Private-label seller · Italy
Before → after
On every listing change
Title, images, bullets, description, category or a backend field — you see the old value next to the new one, so you know exactly what Amazon (or someone else) changed on your listing.
50+
Signals monitored per listing
Buy Box and pricing, fees and margin, account health, listing suppression, the backend listing record and compliance fields, product content, reviews and feedback, rank, inventory and hijackers — watched simultaneously.
14 days
Free trial
Full coverage from day one. Every alert lands with context: who moved, whether they're a real threat, and whether acting would breach your floor.
$0 per ASIN
Flat pricing, unlimited ASINs
Other tools charge per ASIN — roughly $35 for 100 and $200 for 1,200, again for every marketplace. SentryKit prices by storefront, from $19/mo, with unlimited ASINs and every marketplace included.
Global Coverage

Every Amazon marketplace.
One account.

Selling in the UK and across Europe, or in North America? SentryKit monitors every listing in every marketplace you sell in — and speaks your sellers' language.

  • ✓  Alerts in your marketplace's native language
  • ✓  Prices in local currency — £, €, $, C$, MX$
  • ✓  All storefronts and marketplaces under one login
Europe 🇩🇪 Germany🇬🇧 United Kingdom🇫🇷 France🇮🇹 Italy🇪🇸 Spain🇳🇱 Netherlands🇸🇪 Sweden🇵🇱 Poland🇧🇪 Belgium🇮🇪 Ireland
North America 🇺🇸 United States🇨🇦 Canada🇲🇽 Mexico
Asia Pacific 🇯🇵 Japan🇦🇺 Australia🇸🇬 Singapore🇮🇳 India🇹🇷 Turkey
Middle East & Africa 🇦🇪 UAE🇸🇦 Saudi Arabia🇿🇦 South Africa🇪🇬 Egypt
South America 🇧🇷 Brazil

22 marketplaces · more being added regularly

Amazon Listing Monitoring

Amazon listing monitoring: 50+ signals across every layer of your listing.

Pick a category to see the alert that lands in your inbox. Each one says what changed, who's on the listing, and Amazon's own reason when Amazon gives one. Every signal is also in our Amazon product monitoring library.

SentryKit Alerts · to you2 min ago
Subject: Seller C on your ASIN · B0EXAMPLE1
New seller on your listing
Seller C is now selling your product
VP
Vegetable Peeler, Dual BladeASIN: B0EXAMPLE1 · Amazon.com · SKU: VP-02
Their price$21.49below your price
Your price$24.99FBA
Their fulfilmentFBMships from CN
Seller C · Merchant ID A2EXAMPLE7Q · 74% positive feedback (112 ratings)

Know who it is before you react

The alert names the seller, their price, fulfilment and feedback. Mark authorised resellers once and they stop showing up as threats.

Hijacker DetectedNew Seller on ASINSeller ProfileUnauthorised ResellerOffer Count Change
How the Amazon hijacker alert works →
SentryKit Alerts · to youJust now
Subject: Search suppressed · B0EXAMPLE2
Listing issue
Hidden from search: the main image is missing or incorrect
CD
Ceramic Pour-Over Coffee DripperASIN: B0EXAMPLE2 · Amazon.co.uk
StatusSuppressedsearch
Issue code18320MISSING_IMAGE
Detected3:42 PMUTC
Amazon says: The main image is missing or incorrect. Please submit a compliant image to lift the suppression.
A price change won't fix this one. It's a listing issue, not a Buy Box gap.

Amazon's reason, in Amazon's words

You get the issue code and the field Amazon named, so you know what to fix. When Amazon gives no reason, we say so rather than guess.

Listing SuppressedSearch SuppressedAdd-to-Cart RemovedApproval or Gating RequiredRemoved from CatalogImage Requirement Violation
How the search suppression alert works →
SentryKit Alerts · to youToday, 9:05 AM
Subject: 3 fields changed · B0EXAMPLE3
Listing change
3 fields changed on this listing
PK
Stainless Pour-Over Kettle 1LASIN: B0EXAMPLE3 · Amazon.de
Main imagemain_product_image_locator
Image replaced. Before and after shown in the email.
Backend search termsgeneric_keyword
pour over kettle, gooseneck kettle, electric gooseneck
Country of origincountry_of_origin
CN → VN

Changes you didn't make, with before and after

Title, images, bullets and the backend fields buyers never see. Each change shows the old value, the new one, and the raw Amazon field name.

Main ImageGallery ImagesTitleBullets & DescriptionBackend Search TermsCategoryParent / VariationCountry of OriginHazmat ClassList PriceProduct TypeA+ Content
How the product details change alert works →
SentryKit Alerts · to you5 min ago
Subject: Buy Box lost · B0EXAMPLE4
Buy Box alert
Seller B now holds your Buy Box
FC
Manual Food Chopper, 5 CupASIN: B0EXAMPLE4 · Amazon.com · SKU: FC-5
Buy Box price$22.49Seller B · FBA
Your price$24.99FBA
Difference+$2.50you are higher
Offers on ASIN6incl. yours
Add your cost of goods for this ASIN and the next alert tells you whether matching is still profitable.

Lost and suppressed are different problems

Losing to another seller and Amazon showing no Featured Offer at all come as separate alerts, because the fix is different.

Buy Box LostBuy Box WonBuy Box SuppressedBuy Box RotatingWin Rate DropCompetitor Price ChangeYour Price ChangeLowest Offer Change
How the Buy Box alert works →
SentryKit Alerts · to youToday, 7:40 AM
Subject: FBA fee changed · B0EXAMPLE5
FBA fee change
Your FBA fee went up $0.47 per unit
CB
Bamboo Cutting Board, LargeASIN: B0EXAMPLE5 · Amazon.com
Old fee$5.32per unit
New fee$5.79per unit
Change+$0.47+8.8%
Fee jumps often follow a re-measure of the product. Worth checking before it runs for months.

Fee changes, caught per ASIN

Old fee next to new fee, for each ASIN, as soon as it changes. Catch a wrong re-measure early instead of finding it in your payout.

FBA Fee ChangeReferral Fee ChangeStorage Fee ChangeProfit Margin DropNet Profit ChangeReturn Rate Change
How the FBA fee change alert works →
SentryKit Alerts · to youToday, 8:12 AM
Subject: Sales spike, low stock cover · B0EXAMPLE6
Sales volume spike
Sales up 71%, about 5 days of stock left
SM
Silicone Baking Mat SetASIN: B0EXAMPLE6 · Amazon.ca
Units this week2414 avg
Change+71%vs 14-day avg
Stock cover5 days18 units at 3.4/day
At normal FBA check-in times, this could run out before new stock arrives.

Stock measured against how fast it sells

Low stock means little on its own. The alert puts units left next to your current sales pace, so you know how many days you really have.

FBA Out of StockFBA Low StockFBM StockSales Volume DropSales Volume SpikeInbound Shipment StatusStranded Inventory
How the FBA stock alert works →
SentryKit Alerts · to youToday, 6:30 AM
Subject: Account health: Order Defect Rate rising
Account health
Order Defect Rate is close to Amazon's 1% limit
ST
Your storefrontAmazon.com · account-level metric
Order Defect Rate0.9%target under 1%
Previous check0.4%7 days ago
Account Health Rating248was 312
Checked for every storefront you connect.

The numbers that decide whether you keep selling

Account Health Rating, defect and shipping rates, and new policy or IP complaints, flagged while there's still time to act.

Account Health Rating DropOrder Defect RateLate Shipment RateValid Tracking RatePre-Fulfilment CancellationPolicy ViolationIP ComplaintProduct Safety Complaint
See every account health signal →
SentryKit Alerts · to you1 hr ago
Subject: New 2-star review · B0EXAMPLE7
New review
New 2-star review on your listing
MP
Glass Meal Prep Containers, 10 PackASIN: B0EXAMPLE7 · Amazon.com
Rating2 starsnew review
Star average4.4was 4.5
Total reviews1,284on this ASIN
“Lids cracked after a few weeks in the dishwasher.”

Hear about bad reviews early

New and negative reviews, star rating drops and seller feedback, so a product problem doesn't pile up for weeks.

New Product ReviewNegative ReviewFeatured Review ChangeStar Rating DropSeller FeedbackNegative Seller FeedbackFeedback Removal
How the review alert works →
SentryKit Alerts · to youToday, 11:20 AM
Subject: Amazon's Choice badge removed · B0EXAMPLE8
Badge change
Amazon's Choice badge removed
SB
Insulated Steel Water Bottle, 32 ozASIN: B0EXAMPLE8 · Amazon.com
BadgeRemovedwas Amazon's Choice
Best Seller Rank#1,840was #612
CategoryWater BottlesSports & Outdoors

Visibility you can lose without noticing

Badges, Best Seller Rank and Subscribe & Save status change quietly. You hear about it when it happens.

Best Seller Rank ChangeBest Seller BadgeAmazon's Choice BadgeSubscribe & Save StatusCategory Rank Drop
How the Amazon's Choice alert works →
Start free trial → See all 50+ signals →

14 days free, no card. Every signal is included on every plan, and every alert is customizable.

Built for every seller model

Different models, different threats. SentryKit knows yours.

What you need to watch depends on how you sell. Private-label brands face hijackers and listing tampering. Wholesale fights a crowded offer landscape. Online arbitrage runs thin margins at high velocity. Agencies juggle all of it across many accounts.

You own the listing. Protect every inch of it.

Your biggest threats are hijackers, unauthorised resellers, and listing changes you didn't make. When a hijacker appears on your ASIN, you need their feedback rating, feedback count, and fulfillment type in the same alert — not just that they're there.

  • Hijacker Detected with full seller profile
  • Content Changed — title, image, category
  • Buy Box Suppressed vs Lost — clearly separated
  • Out of Stock alert before eligibility drops
  • Backend field and compliance changes on listings you own

Multiple sellers, one listing. Every move is visible.

You're competing on someone else's ASIN with sellers who know the listing as well as you do. Knowing their FBA status, account standing, and how their price compares to your floor changes your entire pricing strategy.

  • Buy Box Lost with competitor fulfillment type
  • Competitor Price Change with floor check
  • Price Floor Breach alert before you go negative
  • Full offer landscape per ASIN
  • Suppression alerts carrying Amazon's stated reason

Fast catalog. Thin margins. Know before you move.

OA is high velocity with tight margins. Amazon inventory alerts that catch stock depletion early and sales velocity drops that signal a Buy Box problem before your payout report does.

  • Low Stock alert against live sales velocity
  • Sales Volume Drop before it hits revenue
  • Buy Box Lost with exact gap to floor
  • Daily Portfolio Digest across your full catalog

All your clients. One view. No surprises.

Managing multiple seller accounts means listing health across all of them — not 15 separate dashboards. Every issue flagged before a client notices a revenue dip.

  • Cross-account Buy Box dashboard
  • Margin Threshold alerts per account
  • Priority alerts across all ASINs
  • Account health and policy metrics per client account
  • Agency pricing from ~$199/mo
Pricing

Simple, flat pricing —
based on your storefronts.

Start with 14 days free. Every plan includes all 50+ signals, unlimited ASINs, every marketplace, and the full API and webhooks. Your price is based on one simple thing — how many storefronts you run.

Starter
$19/mo
billed monthly
$15/mo
billed annually · save 20%
2 storefronts included
For sellers running one or two storefronts who need to act fast.
Start 14-day free trial
  • 2 storefronts, unlimited ASINs, every marketplace
  • All 50+ real-time signals
  • Full REST API & webhooks — included, not an add-on
  • 50,000 API calls a month · signed payloads, retries, delivery log
  • COGS + floor-price calculator
  • 30-day alert history · email, dashboard & Sheets
API Partner
$1,200/mo
six-month minimum
Everything in Pro, plus
For teams who already run their own dashboard, warehouse or reporting layer.
Talk to us
  • Unmetered API within a published rate limit
  • Custom event types built for your pipeline
  • Portfolio roll-up across client accounts
  • History backfill on request
  • 30-day hands-on build with our engineers
  • A named engineer in a shared channel
  • Contractual uptime SLA
  • We feed your system — we don't replace it

Agency / Enterprise

Managing many client accounts? Custom volume pricing with white-label alerts, consolidated invoicing, an uptime SLA, and a dedicated onboarding partner — from ~$199/mo.

Talk to us →
🛡️

No hard cutoffs, ever. Unlimited ASINs, orders and marketplaces on every plan — only storefronts affect your price. The API and webhooks are included on every plan, and there are no overage charges: if you pass your monthly call allowance we slow you down for the rest of the cycle, we never bill you. Your coverage keeps running through Q4 peaks and flash sales.

Amazon Listing Monitoring

Amazon listing monitoring, explained

Amazon, other sellers and your own team change your listings every day, usually without telling you. Amazon listing monitoring watches every ASIN you sell and alerts you the moment something that affects sales or margin changes, with what changed and why.

What is Amazon listing monitoring?

It is automated tracking of your Amazon listings for changes you did not make or did not expect: a lost Buy Box, a new seller on your ASIN, a listing that drops out of search, an edited title or main image, a higher FBA fee. Instead of checking Seller Central by hand, you get an alert with the before and after, and Amazon's stated reason where Amazon gives one.

What does SentryKit monitor on each listing?

50+ signals on every plan: Buy Box lost and won (and lost vs suppressed as separate alerts), hijackers and new sellers, search suppression with Amazon's reason, issue code and field name, title, bullet, image, category and variation changes with before and after, FBA fee changes old vs new, price changes, stock, reviews, and account health (AHR, ODR, late shipment rate). See every signal in the Amazon product monitoring library.

Can I automate catalog health monitoring across storefronts and marketplaces?

Yes. Connect each storefront once and SentryKit runs automated Amazon catalog health monitoring on every ASIN, with no per-ASIN limit, across 22 Amazon marketplaces with prices in the local currency. Alerts can be routed per storefront or per brand, so each team only sees its own listings.

How fast are alerts, and where do they arrive?

Alerts are real time: SentryKit acts on Amazon's live notifications rather than a once-a-day check. They arrive by email, Slack, Microsoft Teams or ClickUp, and every plan includes webhooks and a REST API.

How is SentryKit different from AMZAlert, AmzMonitor or SellerSonar?

The main differences are check speed, pricing model and depth: some listing monitors check on a schedule and price per ASIN, while SentryKit alerts in real time with flat per-storefront pricing and unlimited ASINs. We compare all five tools on pricing, alert speed and coverage in Amazon listing monitors compared.

Can I customize which Amazon alerts I get?

Yes. Turn any alert type on or off, set your own thresholds (for example, how big a sales drop should trigger an alert), tag sellers as authorised, watchlist or ignore so resellers you trust stop setting off alerts, and send each alert to email, Slack, Microsoft Teams, ClickUp or a webhook, per storefront or brand. Not sure what to watch? Tell us what matters and we'll help you tune it.

How much does it cost?

From $19/month, with unlimited ASINs. Start with a 14-day free trial, no credit card needed. See pricing.

Amazon Listing Monitoring

See every signal.
Protect every listing.

50+ signals on every listing, with what changed and why on every alert. 14 days free, then $19/mo. Cancel anytime.

Start free — 14 days, no card →
Real-time alerts 50+ signals per listing Unlimited ASINs No commitments