Pokémon TCG · HeartGold & SoulSilver · #101
Professor Oak's New Theory #101 price
HeartGold & SoulSilver101Market prices
90-day range · TCGplayer
Professor Oak's New Theory (#101, Uncommon) is a card from Pokémon set HeartGold & SoulSilver. Near Mint (Normal), it has a market price of about $0.71 on TCGplayer and €0.18 on Cardmarket (updated November 12, 2026). Over the last 7 days, its TCGplayer market price fell 1.4% and the Cardmarket price trend fell 18.2%. Over the last 30 days, its TCGplayer market price fell 5.3% and the Cardmarket price trend fell 18.2%. Over the last 90 days, its TCGplayer market price fell 17.4% and the Cardmarket price trend fell 21.7%. Its 90-day TCGplayer market price range is $0.71 to $0.86. Its 90-day Cardmarket price trend range is €0.02 to €0.51. Among the 38 Uncommon cards of HeartGold & SoulSilver, it is the 32nd most valuable. Converted to dollars, its Cardmarket price is 71.9% lower than its TCGplayer price. On Sparkl, 12 collectors have this card.
Professor Oak's New Theory #101 prices by finish
| Finish | TCGplayer | Cardmarket |
|---|---|---|
| Normal | $0.71 | €0.18 |
| Reverse Holo | $6.99 | €2.74 |
Near Mint prices: TCGplayer market price, Cardmarket price trend, updated November 12, 2026.
Price changes by finish
| Finish | Price | 7 days | 30 days | 90 days | 90-day range |
|---|---|---|---|---|---|
| Normal | TCGplayer market price | −1.4% | −5.3% | −17.4% | $0.71 – $0.86 |
| Normal | Cardmarket price trend | −18.2% | −18.2% | −21.7% | €0.02 – €0.51 |
| Reverse Holo | TCGplayer market price | +0.0% | +0.4% | +1.0% | $6.92 – $6.99 |
| Reverse Holo | Cardmarket price trend | +0.0% | +0.0% | +3.0% | €2.66 – €2.74 |
Change of the same Near Mint price (same market, same finish) against 7, 30 and 90 days ago; range: its lowest and highest daily value over the last 90 days. Only where the price history supports a figure; lowest listings have none.
Price charts, graded prices from PSA, CGC, BGS, SGC, TAG and ACE, PSA population counts and recent sold listings are in Sparkl Pro.
About this card
- Number
- 101
- Rarity
- Uncommon
- Finishes
- Normal, Reverse Holo
- Rank in its rarity
- 32nd of 38 Uncommon cards
- Against its rarity’s median
- 0.4× the median ($1.71)
- Cardmarket vs TCGplayer
- −71.9% after conversion ($1.1081 per euro)
- Finish spread
- Normal $0.71 to Reverse Holo $6.99 (9.8×, TCGplayer)
- Released
- February 10, 2010
- Print language
- English
How this page is made: Near Mint prices from TCGplayer and Cardmarket, refreshed daily; ranks, medians and comparisons are computed by Sparkl from those prices.
You are viewing the free public price page
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