What is the Slabline Score?

The Slabline Score is a credit-style 0–1000 protection score for a graded trading-card collection, blended from five weighted factors: Insurance (35%), Concentration (25%), Storage (20%), Liquidity (10%), and Provenance (10%). Higher is better; bands run A (≥880) to F (<400).

How does Slabline value my graded cards?

Each card is valued from recent comparable sales for the exact graded card (by certification number and grade), aggregated across eBay, Heritage, Goldin, and PWCC. More comps yield a tighter, higher-confidence value.

Does Slabline sell insurance?

No. Slabline is software that produces broker-ready insurance schedules and risk reports. It is not an insurer, broker, or appraiser and does not provide insurance, financial, or legal advice.

Which cards and categories does Slabline support?

Graded slabs from PSA, BGS, SGC, CGC, and TAG across baseball, basketball, football, soccer, Formula 1 / racing, hockey, Pokémon, Magic, and VeeFriends.

How much does Slabline cost?

There is a free Ledger tier for up to 25 cards. Collector is $99/year (or $9.99/month) and removes the card limit for an unlimited collection. Insured is $149/year (or $14.99/month) and adds broker-ready insurance schedules and a weekly intelligence brief. A Vaulted tier adds connected Hobby Smart Case hardware.

What is the Hobby Smart Case?

A connected travel case (Travel 40, 75, and Pro) with per-slot temperature, humidity, light, and tamper monitoring, plus GPS location and a chain-of-custody log — turning storage risk into live, sensor-verified data. Launching Q4 2026.

What's the difference between a Grade 9 and a Gem Mint 10 Imposter Professor Oak?

For the 2021 Japanese 25th Anniversary Promo Imposter Professor Oak #4, a Grade 9 is worth about $20 while a Gem Mint 10 is about $60 — the grade gap is roughly $40.

How does Slabline value the Imposter Professor Oak card?

Slabline values each graded card from recent comparable sales of the exact card and grade, aggregated across eBay, Heritage, Goldin, and PWCC. More sales yield a tighter, higher-confidence estimate.

How much is a raw (ungraded) 2021 Japanese 25th Anniversary Promo Imposter Professor Oak #4 worth?

A raw (ungraded) 2021 Japanese 25th Anniversary Promo Imposter Professor Oak #4 is worth about $5, based on recent comparable sales. Values move with the market — track it free in Slabline to see the current number.

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2021 Japanese 25th Anniversary Promo Imposter Professor Oak #4

Q: How does Slabline value my graded cards?

Each card is valued from recent comparable sales for the exact graded card (by certification number and grade), aggregated across eBay, Heritage, Goldin, and PWCC. More comps yield a tighter, higher-confidence value.

Q: Does Slabline sell insurance?

No. Slabline is software that produces broker-ready insurance schedules and risk reports. It is not an insurer, broker, or appraiser and does not provide insurance, financial, or legal advice.

Q: Which cards and categories does Slabline support?

Graded slabs from PSA, BGS, SGC, CGC, and TAG across baseball, basketball, football, soccer, Formula 1 / racing, hockey, Pokémon, Magic, and VeeFriends.

Q: How much does Slabline cost?

There is a free Ledger tier for up to 25 cards. Collector is $99/year (or $9.99/month) and removes the card limit for an unlimited collection. Insured is $149/year (or $14.99/month) and adds broker-ready insurance schedules and a weekly intelligence brief. A Vaulted tier adds connected Hobby Smart Case hardware.

Q: What is the Hobby Smart Case?

A connected travel case (Travel 40, 75, and Pro) with per-slot temperature, humidity, light, and tamper monitoring, plus GPS location and a chain-of-custody log — turning storage risk into live, sensor-verified data. Launching Q4 2026.

What a PSA 10 is worth — from real comparable sales.

2021 Japanese 25th Anniversary Promo Imposter Professor Oak #4 card

Estimated value · PSA 10

$60

Based on 17 recent comparable sales.

Value by grade

How much the 2021 Japanese 25th Anniversary Promo Imposter Professor Oak #4 is worth at each grade.

Grade	Value
Raw / Ungraded	$5
Grade 7	$8
Grade 8	$10
Grade 9	$20
Grade 9.5	$22
Gem Mint 10	$60

Which grader maximizes value

Gem / 10 by company

A PSA 10 tops the graded market for this card at $60.

PSA$60
BGS$54
SGC$36
CGC$22

Estimates from recent comparable sales. A higher graded-market value doesn’t guarantee the card earns that grade — Pre-Grade it first to judge the odds.

If you had to sell today

Liquidity

Market value

$60

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Quick-sale recovery

≈ $15

25% recovered

A dealer typically pays about 25% of market for a fast, guaranteed sale — the rest is the liquidity gap. An auction or private sale can recover more but takes time and fees. It’s why your Slabline Score weighs liquidity — and why insuring at market matters: a fire-sale recovers far less than the number you’re covered for.

Estimated from dealer buy-vs-sell spreads; actual offers vary by condition and demand.

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Opens the ROI calculator pre-filled with this card's Grade 9 and Gem Mint 10 values.

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Frequently asked

How much is a PSA 10 2021 Japanese 25th Anniversary Promo Imposter Professor Oak #4 worth?: A PSA 10 2021 Japanese 25th Anniversary Promo Imposter Professor Oak #4 is worth approximately $60, based on recent comparable sales. Card values fluctuate with the market.
What's the difference between a Grade 9 and a Gem Mint 10 Imposter Professor Oak?: For the 2021 Japanese 25th Anniversary Promo Imposter Professor Oak #4, a Grade 9 is worth about $20 while a Gem Mint 10 is about $60 — the grade gap is roughly $40.
How does Slabline value the Imposter Professor Oak card?: Slabline values each graded card from recent comparable sales of the exact card and grade, aggregated across eBay, Heritage, Goldin, and PWCC. More sales yield a tighter, higher-confidence estimate.
How much is a raw (ungraded) 2021 Japanese 25th Anniversary Promo Imposter Professor Oak #4 worth?: A raw (ungraded) 2021 Japanese 25th Anniversary Promo Imposter Professor Oak #4 is worth about $5, based on recent comparable sales. Values move with the market — track it free in Slabline to see the current number.
How much is a PSA 7 2021 Japanese 25th Anniversary Promo Imposter Professor Oak #4 worth?: A PSA 7 2021 Japanese 25th Anniversary Promo Imposter Professor Oak #4 is worth about $8, based on recent comparable sales. Values move with the market — track it free in Slabline to see the current number.
How much is a PSA 8 2021 Japanese 25th Anniversary Promo Imposter Professor Oak #4 worth?: A PSA 8 2021 Japanese 25th Anniversary Promo Imposter Professor Oak #4 is worth about $10, based on recent comparable sales. Values move with the market — track it free in Slabline to see the current number.
How much is a PSA 9 2021 Japanese 25th Anniversary Promo Imposter Professor Oak #4 worth?: A PSA 9 2021 Japanese 25th Anniversary Promo Imposter Professor Oak #4 is worth about $20, based on recent comparable sales. Values move with the market — track it free in Slabline to see the current number.
How much is a PSA 9.5 2021 Japanese 25th Anniversary Promo Imposter Professor Oak #4 worth?: A PSA 9.5 2021 Japanese 25th Anniversary Promo Imposter Professor Oak #4 is worth about $22, based on recent comparable sales. Values move with the market — track it free in Slabline to see the current number.
How much is a PSA 10 2021 Japanese 25th Anniversary Promo Imposter Professor Oak #4 worth?: A PSA 10 2021 Japanese 25th Anniversary Promo Imposter Professor Oak #4 is worth about $60, based on recent comparable sales. Values move with the market — track it free in Slabline to see the current number.
Which grading company is the 2021 Japanese 25th Anniversary Promo Imposter Professor Oak #4 worth the most in?: A PSA 10 2021 Japanese 25th Anniversary Promo Imposter Professor Oak #4 tops the graded market at about $60. Across companies: PSA 10 $60, BGS 10 $54, SGC 10 $36, CGC 10 $22.
How much would I actually get selling the 2021 Japanese 25th Anniversary Promo Imposter Professor Oak #4?: A quick sale to a dealer typically recovers about 25% of market value — roughly $15 on this card's $60 value. An auction or private sale can recover more but takes longer and charges fees. The gap between market value and quick-sale recovery is the card's liquidity risk.

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Own this card? Track its value automatically.

Add it to your free Slabline collection — live valuations, a 0–1000 protection score, and a broker-ready insurance schedule.

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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.