How we collect prices and check compatibility

Where prices come from

Prices come from B&H Photo's product data feed. We read the feed every four hours and rebuild it from B&H's full daily feed each night. Each reading is stored as a dated snapshot, which is what the price-history charts are drawn from.

A price is only shown as “current” when the card is in stock and the snapshot is under 48 hours old. Anything older is shown as “no current price”, never as today's price.

We don't show Amazon prices, because we don't hold a current Amazon price we are allowed to display. Where Amazon sells a card, the Amazon button takes you to its live price on Amazon. Retailer prices change often, so always confirm the price at checkout.

Price history and deals

Lows, highs and averages are calculated from the snapshots we have recorded. They cover only the period we have been tracking a card, so “90-day low” means the lowest price we saw in that window, not the lowest price the card has ever sold for. We judge discounts against our own recorded history, not against a retailer's “was” price.

The price-value score

The 0–100 value figure ranks a card's price per GB against other cards of the same format and the same size class, for example 512GB CFexpress Type B against other 512GB CFexpress Type B cards. Comparing across sizes would only reward the biggest card.

It measures price, not quality. It doesn't measure speed, reliability, endurance or warranty, and it isn't a review score. Groups with fewer than three priced cards get no score.

Speeds

Read, write and sustained-write speeds are the manufacturer's ratings. Peak write speed and sustained write speed are different numbers. For video, the sustained figure (or the VPG / V-class rating) is the one that decides whether a card keeps up. We have not run our own speed tests, and we don't present ratings as test results.

Camera compatibility

Each camera page lists the camera's card slots and the format each slot accepts, taken from the manufacturer's published specifications. A card is listed for a camera when its format fits a slot.

Fitting the slot is not the same as supporting every recording mode. High-bitrate modes can need a minimum sustained speed or a card the manufacturer has approved. Before buying for demanding video, check your camera manual's media requirements for the mode you plan to use.

How we make money

ProCardPrices takes part in affiliate programmes, including B&H Photo and Amazon Associates. If you buy through a link here we may earn a commission, at no extra cost to you. Commission doesn't affect how cards are ranked: lists are ordered by price, price per GB or specification. Any sponsored content will be clearly labelled.

Corrections

Spotted a wrong price, spec or compatibility entry? Email alerts@procardprices.com and we'll check it against the manufacturer's documentation and fix it.