Free Chrome Extension
Amazon Price History — sparkline panel, delta badge, and savings tracker.
A free Manifest V3 extension that drops a 90-day price chart directly under the current price on every Amazon product page. Flags the delta vs. the 90-day low, tracks your cumulative savings, and keeps everything local — no account, no data leaves your device.
What you get
Four things the panel does on every Amazon product page.
The extension reads what is already on the page, appends one sample to local storage, and renders a compact panel inline beneath the current price — no extra tab, no popup, no account.
90-day sparkline
A compact price-history chart rendered directly under the current price block. Hover a point to see the daily close; the panel appears on second visit and grows richer with each return.
Delta badge
A colour-coded badge next to the price header: emerald at-or-near low, amber within ten percent, rose above. Tells you at a glance whether today's price is actually a deal.
Cumulative savings tracker
Every price drop you would have caught is logged; the panel surfaces a running total saved across the last 90 days per ASIN. Surfaced on hover — never in the way.
Honest affiliate disclosure
Links on Amazon product pages pass through the Amazon Associates program. A commission is earned at no extra cost to you — the disclosure is rendered directly under the chart panel on every page.
Install from the Chrome Web Store
Three steps and you are tracking Amazon prices.
No developer mode, no unpacked load. Install directly from the Chrome Web Store — search for Amazon Price History or click the button below.
- 1
Open the Chrome Web Store listing
Click the button below — it opens the Amazon Price History CWS listing in a new tab.
- 2
Click "Add to Chrome"
Chrome shows the permission summary:
storage+activeTab, scoped tohttps://www.amazon.com/*. Approve and the icon lands in your toolbar. - 3
Open any Amazon product detail page
Visit once to log the first price sample. The sparkline, delta badge, and savings tracker appear directly beneath the price block on the second visit. Every future visit appends a sample to the local 90-day window.
Affiliate disclosure
Honest from day one.
Extensify participates in the Amazon Services LLC Associates Program — an affiliate advertising program designed to provide a means for sites to earn fees by linking to amazon.com. Affiliate links route through Amazon's standard program; commissions do not change your price. Cumulative savings are calculated against prices you actually saw on your device, not list price or a third-party baseline.
FAQ
Common questions about Amazon Price History.
What the extension stores, which browsers it supports, and how the affiliate relationship works.
Is Amazon Price History free?
Yes — fully free, no Pro tier, no in-app purchases, no paywall. The extension ships the same feature set to every install; nothing is gated on an account, login, or license key.
What is stored, and where?
Price samples are stored exclusively in chrome.storage.local on your own device. Nothing is sent to a server, a third-party price tracker, or any remote endpoint. You can clear or inspect the data at any time from the extension page.
Does any browsing data leave the device?
No. The extension makes zero remote calls — no fetch, no XMLHttpRequest, no WebSocket, no analytics endpoint, and no third-party price APIs. Every price sample lives in chrome.storage.local on your device.
Which browsers are supported?
Chrome and any Chromium-based browser: Edge, Brave, Arc, and Opera all work. The extension is built as a Manifest V3 extension and is not available for Firefox or Safari.
Is there an affiliate relationship?
Yes — Extensify participates in the Amazon Services LLC Associates Program, an affiliate advertising program. Links on Amazon product pages route through the standard Amazon Associates tag; commissions do not change the price you pay. The full disclosure is rendered directly under the chart panel.
How does the cumulative savings tracker work?
Every time you visit an Amazon product page and the current price is below the 90-day high the extension observed, the positive delta is added to your running total. The tracker shows the cumulative negative-delta sum across the last 90 days per ASIN — savings are based on prices you actually saw on your device, not a list price or third-party baseline.