Online prices are not fixed, and "was" prices are not always honest. A listed item can change price several times a day, and a sale banner often marks a return to the normal price after a quiet increase. A price-history tool shows what an item actually sold for over the past year, which is the only way to know whether today's discount means anything at all. We use three of them, plus a plain spreadsheet, and between them they have cut roughly a fifth off our large purchases.
What we use and for what
- A browser extension for the big marketplace. It overlays a price history chart on the product page and lets you set an alert for a target price. Free, and the single most useful tool on this list. The chart shows instantly whether a "deal" is the item's normal price with a badge on it.
- A price tracker for grocery delivery. Grocery prices online move weekly, and the tracker shows the range. We use it to time the stock-up items: coffee, laundry detergent, diapers when we had them.
- A general alert service. Paste any product URL from most retailers and set a target. It emails when the price drops. Slower than the extension but works across stores.
- A plain spreadsheet. For the handful of things we buy every year at a known price: tires, heating oil, the car insurance renewal, school supplies. We note the price and the date each time. Nothing beats a year of your own data.
What the history taught us
Most "deals" return every six to eight weeks. If you miss one, another is coming. The genuine low points cluster in late November, late January and the week or two after a new model is released, when the outgoing model drops. Everything else is patience.
The other lesson is that list prices drift upward before a sale. A product that sat at $89 for months moves to $109 in early November and then goes on sale for $84 with a "save $25" badge. The history chart makes this visible in a second.
How to buy with a tracker
- When you decide you want something, look at the one-year chart before anything else.
- Set an alert at or near the lowest price in the chart.
- Wait. Most alerts fire within two months. If it is urgent, buy at any point below the average line.
- When the alert fires, check that the seller is the retailer itself or a reputable one, not a marketplace reseller at a lower price with a different return policy.
Where trackers do not help
Groceries in a physical store, where prices are not online. Local services. Anything sold through a single small shop with no price history. And anything you need today; a tracker is a tool for planned purchases, which is another argument for the sinking funds that let you plan them.
A note on browser extensions
Any extension that reads the pages you visit can see a lot. We use the ones with a long track record and a clear privacy statement, and we run them in a separate browser profile used only for shopping. That is a small inconvenience for a real reduction in what the extension sees.
