Back in 1980 I got hired as Data Processing Manager for the Honolulu Club for the princely sum of $10,800 per annum. Suppose I wanted to know just how much that $11K is worth in today’s dollars? By going to Economic History Services and clicking the How Much Is That link I could go to the Purchasing Power link, enter the number into a little box, enter the year into another little box, click the button, and learn that it has the same purchasing power as $24,128.84 does today. For a reality check, I could reach back into memory and remember that I could buy three packs of cigarettes and a 12-pack of Bud for just under $10 at the time. Now that would cost me about $27; $5 apiece for the smokes and $12 for the beer. Yup, the calculator seems to work.
There’s a ton of fascinating (well, if you like the dismal science) material on that site.