You see a product on Amazon. It says “Was $89.99, NOW $49.99 — 44% off!” That seems like a great deal. But was it ever actually $89.99? Or did the seller jack up the price for two days so they could claim a discount?

This is called price anchoring, and it happens constantly. Here is how to check whether a sale is real in about ten seconds.

CamelCamelCamel: the price time machine

Go to camelcamelcamel.com, paste the Amazon product URL, and it shows you a price history chart going back years. You can see exactly when the price went up, when it went down, and what the actual low price has been. A product that has been $50 for six months and “discounted” from $90 was never worth $90.

I checked a coffee maker I was about to buy — “50% off, limited time!” The chart showed it had been at that exact same “sale” price for eleven of the last twelve months. The “regular price” was a fiction.

Keepa for browser users

Keepa is a browser extension that embeds the price history chart directly on the Amazon product page. You do not even have to leave the page. It also shows price drop alerts and lets you set target prices. When the item hits your target, you get an email. I have saved more money with Keepa alerts than I have with any coupon site.

Honey and Capital One Shopping

These browser extensions automatically test coupon codes at checkout and compare prices across sellers. They are free (they make money through affiliate commissions, not by charging you). Honey found me a working 20% off code on a patio furniture set last summer that I would never have found on my own. It took three seconds and saved me $47.

The 48-hour rule

If something is not urgently needed, add it to your cart and wait 48 hours. Retailers often send an abandoned cart discount code — usually 5-15% off — to nudge you into completing the purchase. This works especially well on direct-to-consumer brand sites, less so on Amazon.