If the Defending Pokémon has a Weakness, you may change it to a type of your choice other than Colorless.
Conversion 2
Change Porygon's Resistance to a type of your choice other than Colorless.
“A Pokémon that consists entirely of programming code. Capable of moving freely in cyberspace.”
How much is Porygon #39/102 worth?
Porygon #39/102 is a Uncommon card from Base (1999) — today it trades at roughly $3.48 ungraded. Across the 3 printings we track, copies run anywhere from $0.75 to $499.99 depending on the version you're holding.
Grading changes the math on this one: a PSA 10 is valued around $115.00, roughly 33.0x the raw price, while a PSA 9 sits near $31.00. 2,452 copies have been graded to date, and 15% of them came back a 10 — worth knowing before you pay grading fees.
We update this valuation every night from live market data and verify it against real completed sales — see the chart above for how Porygon has moved over time.