Compare Jerry Koosman values across different grades. See whether grading is worth it based on current prices and PSA gem rates.
Price by Grade
| Grade | Guardian Estimate | Premium vs Raw |
|---|
| Raw / Ungraded | $1.68 | — |
| PSA 8 | $12.88 | +667% |
| PSA 9 | $25.00 | +1388% |
| PSA 10 Gem Mint | $157.29 | +9263% |
Frequently Asked Questions
Is Jerry Koosman worth grading? A PSA 10 Jerry Koosman is worth $157.29 vs $1.68 raw — a 9263% premium.
What is Jerry Koosman PSA 10 worth? $157.29 as of September 2026.