Quick fill
Pick a key and a condition — the table fills itself. Then tweak anything.
Key values are rough starter estimates, and grade values are curved from the BGS 9.8 anchor. Replace them with your own sold comps before trusting the verdict — the tool is only as honest as its inputs.
The book
What it costs you to get a slab in hand.
$
$
%
The grade odds
Your read on how it grades, and the sold-comp value at each grade.
GradeChanceValue
Probabilities total100%
The verdict
—
Expected graded value
—
probability-weighted, before fees
Expected net profit
—
after fees & all costs
Expected ROI
—
on total cash in
Chance of profit
—
break-even at —
Profit by grade outcome
How to fill this in honestly
Grade odds: base them on the raw copy in front of you and BGS population data — not optimism. Values: use real sold comps (130point, PriceCharting, Heritage) at each grade, not asking prices. The trap: a positive EV carried entirely by a low-odds 9.8 is a gamble, not an edge — watch the "chance of profit," not just the average. When the value gap between grades is small, don't grade.