How DipScout works

Hi, I'm Tinho. I watch AliExpress prices all day, keep every change and only speak up when a drop is real. Here's how I check.

DipScout is a price radar for AliExpress. We track each product's price over time and only call it a deal when that history proves the drop. The "was $39.99, now $19.99" the store writes on the listing doesn't count: the store writes it, and nobody checks it.

1. We read prices several times a day

Prices come from the official AliExpress affiliate API, in US dollars and for shipping to the United States. Every day we read the best sellers of each category and the official promotion lists; every two hours we read again the products with recent drops and the best sellers. Every time a price changes, we store the change with its date and time. That history is ours: AliExpress doesn't show old prices to anyone.

2. We work out the typical price

For each product, we look at the last 14 days and see which price held the longest. That's the typical price. A spike of a few hours doesn't move it, and neither does a price inflated on the eve of a sale, as long as it lasts less than the rest of the period.

3. Only a drop that holds counts

A product shows up in the drops when:

• we've tracked its price for at least 3 days;
• today's price is at least 15% and $3.00 below the typical price (for products from $5.00 up), or it's the lowest price we've ever recorded for it;
• the lower price held for 12 hours before we counted it (AliExpress often flips the same item between two prices from one read to the next);
• the drop was checked again in the last 48 hours.

A drop stays on the site for up to 7 days. If the price goes back up, it leaves on its own, and the product page says the drop is over.

4. What we throw out

• The store's "was" price. It never backs a discount, anywhere on the site.
• Up before down. If the store raised the price and then "lowered" it back to what it already charged in the last 30 days, it's not a deal. The product page shows the dates and prices.
• A different variant. A listing can have options at different prices. When the price falls because AliExpress started showing a cheaper option, we don't call it a drop.
• A mistyped price. A typical price more than 4× today's usually means a listing with an absurd price that was corrected.

What the site doesn't do

The price shown is the last recorded reading, not a live checkout lookup. Coupons, shipping and taxes aren't included, and prices in other countries and currencies can differ. And before our first reading of a product we don't know its price, so we never say "the lowest price in history".

Want to check a product?

Paste the link into Check a product to see the history and the verdict. See also the latest price drops, the biggest drops and the FAQ.