My husband and I will be in Copenhagen for a week in mid-May. Is a Copenhagen card - or the expanded card that is also good outside of the city- worth buying?
Ye, it is. We had the Copenhagen card and saved a fortune on transportation to sights on the island and admission to sights in Copenhagen.
I see a large number of nominally-covered attractions listed as "temporarily closed" on the website. They are not generally big-name sights, so these may just be seasonal closures that will not affect a May visit, but I'd want to check their individual websites for devinitive info if any are of interest. Also note that the card website indicates the National Aquarium is no longer covered (though it would be an unlikely destination for folks traveling without children).
In my experience, cards for large, popular cities are priced very high and usually make financial sense only for aggressive sightseers who want to visit a lot of sights relatively quickly rather than having time to wander around picturesque neighborhoods, linger over lunch, etc.
At the current exchange rate, the Copenhagen Card-Discover costs about US $65 for 1 day, $95 for 2 days, $119 for 3 days and $139 for 4 days.
The website will help you figure out whether the card will save you money, but you have to be realistic about how many places you'll really have time to visit, and I see that the alleged value of a transit pass factors heavily into the equation. They're showing the price/value of the transit pass in euros, and it apparently costs 21 euros ($22) for 1 day, 40 euros ($22l for 2 days and 53 euros ($56) for 3 days. That's an awful lot of public transportation usage.
You can buy transit passes separately if you want to avoid walking.
I was only in Copenhagen for three nights, and I bought the Copenhagen card and it definitely saved me money. I did the math and added up the price of admission tickets, public transportation and trains, etc. vs. the 439 Danish kroner, and it was definitely a money saver. It also included Tivoli and sites in Roskilde, including the Viking museum, and the cathedral.
I was in Copenhagen in August and the Copenhagen Card was 100% worth the purchase. I see someone who has traveled more recently said some attractions once included are closed at the moment? If so, double check what you want to visit to see if it is still included in the card.