24 calculators
for people who
check the number

Why a calculator instead of an article

Ask what a card is worth and the internet answers with a price guide. A price guide is somebody else’s number for somebody else’s copy of the card, published on a date you cannot see, and the honest version of the answer is almost always a calculation you have to do yourself with information you already have: what similar copies actually sold for, what grading would cost you, what the platform takes, what the postage is, and what the chance is that the card grades where you hope.

Every tool here does one of those calculations and shows what went into it. Nothing is behind an account, nothing is behind a paywall, and nothing you type is sent anywhere — the arithmetic is a few dozen lines of JavaScript that arrived with the page and runs on your device. Switch the network off after the page loads and every one of them still works.

What they are built on

There is exactly one copy of the mathematics. The same module the browser loads is imported by this site’s public JSON API and by the service that answers machine queries, so a figure you get from a calculator, a figure an assistant gets from the API and a figure printed in a table on one of these pages cannot disagree — there is nothing left to disagree.

The reference numbers behind it are dated and sourced rather than typed from memory. The centering tolerances come from each grading company’s own published scale, with the link and the date we read it. The inflation series is the U.S. Bureau of Labor Statistics CPI-U, 113 annual averages pulled from the BLS public API, 1913 to 2025. And the numbers that move fastest — grading fees, marketplace percentages, postage — are not constants at all: they are fields you fill in, with a link to the publisher, because a calculator that quietly uses last year’s fee schedule is worse than no calculator.

What is deliberately missing

There is no tool here that tells you what a specific named card is worth, and that absence is a decision rather than a gap. A page that claimed to know the price of a 1986 Fleer Michael Jordan would be quoting a figure from a date it did not show you, for a copy in a condition it had not seen, and the number would be wrong within a month while continuing to look authoritative. What this site can honestly do is take the sold prices you found and tell you what they say — which is the same calculation a price guide performs and never shows.

For the same reason there is no grading fee anywhere on this site. Fee schedules are revised without notice, and a calculator that quietly used last year's tier would produce a confident answer to the most expensive question a collector asks. Every fee is a field you fill in, with a link to the company's own current page beside it. The table below says which of the numbers behind these tools are fixed enough to publish and which are not.

Where to start

If you are holding one card and want to know what it is worth, start with the value calculator and then the era checker, which will tell you in one step whether the card comes from a period where common cards have any value at all. If you already know it is worth something, the centering calculator is the cheapest grading information available anywhere, and the expected-value tool turns the submission question into arithmetic. If you are selling, the honest order is comps → route → fees → postage, and the number at the end of that chain is usually smaller than the one people quote each other.

The one thing no calculator can do

All of these need inputs. The value tool needs sold prices, the grading tool needs a realistic view of what the card would grade, the population tool needs a pop report. Finding those for a specific card is the work, and it is exactly the work the Valdar app exists to do: photograph the card, and it identifies the player, set and parallel, pulls what that exact card has been selling for, and estimates the four grading sub-dimensions. Then you come back here and do the arithmetic on real numbers instead of hopeful ones.

The site also publishes everything behind these tools as open data: the grading scales, the era table, the selling routes, the shipping options and the CPI series, keyless and free to reuse with a link. 5 shipping methods, 9 production eras and 5 grading companies, as JSON.