How we check prices

Where the price history comes from

We record a product's price each time we check the retailer's page. Checks are scheduled and rate-limited, so the history is a set of sampled points, not every price change.

We only check retailers whose robots.txt allows it. If a retailer blocks automated checks, we don’t show a verdict for its deals.

What the ‘usual price’ means

The usual price is the middle value (the median) of the prices we recorded in the 90 days before the deal was posted. Using the median means a single short sale or a one-off spike doesn’t set the benchmark.

If we have fewer than 3 prices from that window, we say there isn’t enough history and don’t give a verdict.

What the labels mean

• Lowest tracked: the lowest price we've recorded for this product.
• Great: well below the usual price.
• Good: a little below the usual price.
• Typical: about the usual price, so the saving is small or none.
• Worse: above the usual price. Waiting may get a better one.
• Not enough data: fewer than 3 prices, so no verdict.

How confident we are

Confidence depends on how many prices sit in the window: 10 or more is high, 5 to 9 is medium, and fewer than 5 is low. Every verdict says how many points it's based on, so you can judge it yourself.

Checking the ‘was’ price

Retailers often show a ‘was’ price, which may not be a real recent price. When the claimed discount is more than 15 percentage points bigger than the real one, we flag it as an inflated ‘was’ price.

What we can't tell you

• Whether an item is in stock, in your size, or on sale at checkout.
• Delivery costs, fees, or the retailer's return terms.
• Prices before we started tracking a product, which is why new products often show little history.
• Anything about a deal in the first 10 minutes after it's posted. Scores are hidden until the community has had a chance to vote.