What Is a Gem Rate and Why Does It Matter for Pokemon Card Investing?

The gem rate is the percentage of cards submitted to PSA that receive a perfect 10 grade. It's one of the most important metrics in card investing because it directly determines your probability of achieving the highest-value outcome when grading.

How It's Calculated

Gem Rate = PSA 10 Count / Total Cards Graded

For example, if 1,000 copies of a card have been graded and 150 received PSA 10, the gem rate is 15%.

PSA publishes population reports showing exactly how many cards have been graded at each level. This data is public and updated in real-time as new cards are graded.

Why It Matters

The gem rate is the foundation of grading ROI calculations:

• High gem rate (20%+): More predictable outcomes. Your card has a decent chance of getting a 10. The PSA 10 premium is usually lower because 10s aren't as scarce.
• Low gem rate (under 5%): High risk, high reward. Most submissions won't get a 10, but the ones that do command massive premiums due to scarcity.
• Medium gem rate (5-20%): The sweet spot for most investors. Enough chance of a 10 to be worthwhile, scarce enough that 10s command good premiums.

What Affects Gem Rate

• Card age: Older cards have lower gem rates due to wear over time
• Print quality: Some sets have better quality control than others
• Language: Japanese cards often have higher gem rates than English
• Card type: Full art and illustration rares tend to have higher gem rates than standard holos

The Catch

A high gem rate alone doesn't mean you should grade. You also need a high enough PSA 10 price relative to your total cost (raw + grading fees). A 50% gem rate with a 2x multiple is worse than a 10% gem rate with a 20x multiple.

SlabQuant combines gem rate with pricing data, market trends, and Monte Carlo simulation to give you a complete picture — not just the odds, but the expected dollar outcome.