How we compute the numbers on Slabfolio

Every number on a Slabfolio market report comes from data we already hold in our own cache. Nothing is estimated at the moment you load the page, and nothing is fetched live. This page explains where each figure comes from and what the words mean.

Prices

Raw, PSA 9 and PSA 10 prices are PriceCharting market values that we snapshot once a day for every card we track. A price appears on a page only when the snapshot behind it is less than 14 days old. If a grade has no recent snapshot, the cell reads "Not tracked" rather than showing a stale or guessed figure. Prices at or above $100 are rounded to the dollar. Prices below $100 show cents.

90 day change

The 90 day change compares the latest PSA 10 snapshot with the snapshot closest to 90 days earlier. When a card has no PSA 10 series, we use the raw series and say so. A change under five percent is reported as flat.

Gem rate

Gem rate is the share of PSA submissions for a card that came back as a PSA 10. We divide the PSA 10 count by the total graded, using PSA's population report for that exact card, number and variety. We only show a gem rate when PSA has graded at least 25 copies, because smaller populations swing wildly with a single submission.

Grading premium

The grading premium is the PSA 10 price divided by the raw price. It tells you how much a perfect grade adds. A high premium with a healthy gem rate is where grading tends to pay. A high premium with a very low gem rate is a gamble. A small premium rarely covers grading fees and shipping.

Verified sales

A verified sale is a completed eBay sale that passed our validator: the title matched the card, the grade matched, the price was not an outlier against recent sales, and the listing was a real single card rather than a lot, proxy or reprint. We show the most recent verified sale for a card only when we have enough validated sales to be confident in it.

Picks

Most expensive right now is the card with the highest PSA 10 price on the list. Best value to grade is the card with the highest grading premium among cards PSA has graded at least 50 times. Rarest in PSA 10 is the card with the fewest PSA 10 copies among cards PSA has graded at least 25 times. Ties go to the higher ranked card.

Update dates

Each market report carries the date its numbers were computed. A post's Updated date moves only when something material changed: a pick changed, a price moved at least five percent and at least five dollars, a population total moved at least five percent, or a newer verified sale appeared. If nothing material changed, the numbers are rechecked but the date stays where it was. We would rather show you an honest older date than a fresh date on unchanged content.

What we do not do

We do not publish prices from a single listing. We do not use asking prices. We do not fill gaps with estimates. We do not show AI generated card images. If a figure is missing on a page, it is because we do not have data we trust for it yet.

Questions about a specific number? Use Ask Slabfolio on any card page or write to [email protected].