What is the value of a 1969 US quarter?

Unless it's uncirculated / proof, or somehow different from the (roughly) 932 million that were minted that year, 25 cents.

As of 09/2009, retail values for uncirculated ones range from about 60 cents in MS60, the lowest Unc. grade, up to about $220 in MS66. Proof versions (1969-S) retail for about $2.30