How much is a PSA 10 1971 Kellogg's John Unitas #28 worth?

A PSA 10 1971 Kellogg's John Unitas #28 is worth approximately $800, the price-guide estimate for this grade. Card values fluctuate with the market.

How does Slabline value the John Unitas card?

Slabline starts from the price guides for the card and grade. When it holds dated recorded sales of that exact card and grade — from CardHedge market data and the auction houses it ingests — the headline becomes the median of the most recent ones and the grade ladder rescales to match. Each row on the page names which of those it is.

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1971 Kellogg's John Unitas #28

What a PSA 10 is worth — price-guide estimate, with every recorded sale we hold.

Estimated value · PSA 10

$800

A PSA 10 1971 Kellogg's John Unitas #28 is valued at about $800, a price-guide estimate rather than a recorded-sales median.

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1971 Kellogg's checklistChecklist→Football index-1.5% 1W

Value by grade

How much the 1971 Kellogg's John Unitas #28 is worth at each grade.

How to read this page: an estimate is Slabline's figure for a grade, built from the source named beside it. An observed price is the latest price a grader's copy of this card fetched, one cell per grader and grade in the grid below. A recorded sale is a dated transaction with its venue. The headline above is the estimate for this slab's own grade.

Grade	Value	Built from
Gem Mint 10	$800est.	estimate

Price guide data: SportsCardsPro

Estimated from this category's observed grade curve and this card's known value, not from this card's own sales at each grade (the recorded sales are above). Estimates, not observed prices.

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Tracked history · PSA 10

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Frequently asked

How much is a PSA 10 1971 Kellogg's John Unitas #28 worth?: A PSA 10 1971 Kellogg's John Unitas #28 is worth approximately $800, the price-guide estimate for this grade. Card values fluctuate with the market.
How does Slabline value the John Unitas card?: Slabline starts from the price guides for the card and grade. When it holds dated recorded sales of that exact card and grade — from CardHedge market data and the auction houses it ingests — the headline becomes the median of the most recent ones and the grade ladder rescales to match. Each row on the page names which of those it is.

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Values are informational estimates built from recent comparable sales — not a certified appraisal, insurance, or financial advice. Card values fluctuate; figures are a snapshot and may differ from a realized sale.