How can you tell how old a hallmark card is?

To determine the age of a Hallmark card, look for the copyright date printed on the back, usually near the Hallmark logo. Additionally, examine the card's design and style, as Hallmark has evolved its aesthetics over the years. Some older cards may feature specific Hallmark series or collections that can help narrow down the date. Lastly, researching online databases or collector resources can provide further context on specific designs and their release dates.