Do baseball cards have any value is a question the hobby answers badly, because the stories that circulate are about the exceptions. The ordinary case is that a card is worth about what it costs to post. The exceptional case is real and identifiable, and telling them apart takes minutes rather than expertise.
The ordinary case, and why it is ordinary
From the late 1980s into the mid 1990s, manufacturers printed cards in quantities that nobody has ever needed, and the people buying them stored them carefully because they had been told the cards would be valuable. High supply plus good condition is exactly the recipe for a low price, and it has held for thirty years.
The exceptional case
Cards that are scarce, sharp and wanted. Scarcity comes from a stated print run, a documented short print or an early date. Sharpness comes from luck and careful handling. Demand comes from a player or a design that a community collects. All three at once is uncommon, which is exactly why those cards are worth something.
How to check without becoming an expert
Sort on what is printed on the cards: serial numbers, manufacturer autographs, anything that is not a base card, anything before about 1980. Then search completed sales for the survivors. You do not need to know the players; you need to read the cards and read the sales.
What to do with the answer
If cards clear the sort and have sales, price them with five comparables through the checker and decide whether to sell. If nothing clears, that is a real result and it took an evening rather than a project. Either way you now know, which is better than wondering.
Questions people ask about do baseball cards have any value
I was told these would be worth a fortune one day.
That belief is part of why they are not: it caused millions of people to buy and store the same cards. The ones that became valuable are mostly the ones nobody thought to keep.
Is a full box worth anything as a lot?
Bulk lots do sell, for small amounts, and that is usually the sensible route for the cards that do not clear the sort.
Should I have them valued professionally?
This site does not appraise or recommend appraisers. Pricing your best twenty from completed sales will tell you most of what a valuation would.
Does it cost anything to check?
No. The sales are free to read and the calculators here are free to use, with no account.