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 | $1.14 | — |
| PSA 8 | $22.44 | +1868% |
| PSA 9 | $25.00 | +2093% |
| PSA 10 Gem Mint | $112.03 | +9727% |
Frequently Asked Questions
Is Jerry Koosman worth grading? A PSA 10 Jerry Koosman is worth $112.03 vs $1.14 raw — a 9727% premium.
What is Jerry Koosman PSA 10 worth? $112.03 as of October 2026.