How much does a 100 year old penny sell for?

If you specifically mean a 1912 penny, the value depends on condition and the mint mark. A 1912 with no mint mark is worth at least a dollar and upwards of about $25. The 1912-D goes for at least $5 and as much as $140. Then a '12-S is worth no less than $10 and goes up to $130. Again, the value depends on condition.