Dags can be translated as 'time', but it has a more specific use than the word tid, which refers to 'time' more generally. Dags is usually used in the constructions det är dags för or simply dags för, which mean '(it is) time for'. Around tax declaration season, tax agency Skatteverket sends tax returns out with the headline dags att deklarera (time to declare your taxes).
This can be followed by a noun, as in dags för kaffe (time for coffee), or a verb, as in dags att förändra sitt liv (time to transform your life). It can also be used on its own in a more emphatic way: nu är det dags! (Now it's time!).
Dags is often pronounced 'dacks' and can be written dax, as in a satirical song Dax att åka hem (time to go home) which went viral online around the time of Sweden's election.
You can also combine dags with nouns and verbs to create compound words: matdags (time for food), sovdags/sängdags (time for sleeping/time for bed) and of course, fikadags (time for fika).
Another way to use dags is in the phrase hur dags which means 'what time' and is a slightly more colloquial variant of när. So you can ask hur dags börjar evenemanget? (what time does the event start?)
Det är nog dags att gå hem
It's probably time to go home
Nu är det sovdags
It's time for bed now (usually said to children)