PricePulse JP
Price History Tracker for Japan
Track price history on Amazon.co.jp, Rakuten, Yahoo! Shopping & Mercari. Get alerts when prices drop. Fully local, no account needed.
// screenshots
// overview
PricePulse JP is a Keepa-style price tracker for Japan's four biggest shopping sites: Amazon.co.jp, Rakuten Ichiba, Yahoo! Shopping, and Mercari. It automatically records every price it sees when you visit a product page, builds a chart of the price history, and sends you a browser notification when the price drops below your target. Everything is stored locally on your device using IndexedDB — no account, no cloud, no sign-in required.
// features
4-Site Price Tracking
Automatically tracks prices on Amazon.co.jp, Rakuten Ichiba, Yahoo! Shopping, and Mercari with a single click
Keepa-Style Price Charts
View full price history in a clean chart powered by Recharts — spot seasonal patterns and identify the true low
Price Drop Alerts
Set a target price and receive an instant browser notification when the price falls below it
3-Hour Background Refresh
Prices update automatically every 3 hours via Chrome alarms — no need to revisit the product page
Quick-Launch Links
One-click shortcuts to all four supported shopping sites directly from the popup
CSV Export (Pro)
Export your full price history to CSV for spreadsheet analysis — Pro feature
// recommended for
- Bargain hunters waiting for the right price on Amazon.co.jp or Rakuten
- Mercari and Yahoo! Shopping buyers tracking secondhand item prices
- Shoppers who want Keepa-style history without paying a subscription
- Privacy-conscious users who want tracking without a cloud account
// faq
Which sites does PricePulse JP support?
PricePulse JP tracks prices on Amazon.co.jp, Rakuten Ichiba, Yahoo! Shopping, and Mercari JP. Just visit any product page on these sites and click the PricePulse button to start tracking.
Is PricePulse JP free?
Yes. The free plan lets you track up to 5 items with full price history charts and drop notifications. Pro ($4.99/mo) raises the limit to 100 items and adds CSV export.
Does PricePulse JP send my data to the cloud?
No. All price history is stored locally in your browser's IndexedDB. The only external calls are aggregated GA4 analytics events — product URLs are never sent.
How often does PricePulse JP check prices?
Prices are refreshed every 3 hours via a Chrome alarm that runs in the background, even when you are not visiting the product page.
Is PricePulse JP similar to Keepa?
PricePulse JP provides a Keepa-style price history chart for Japanese e-commerce sites that Keepa does not cover, including Rakuten, Yahoo! Shopping, and Mercari.
