The last poster to ask this question wanted something more specific, thoughI would go for Carpe diem as it is a quote from Horace and embodies the idea of both English phrases.
The main problem with online "translators" giving Latin translations is the fact that they appear to have no concept of inflexion.
In the "answer" confidently provided by ljdksa, I see "dies" in what looks like the ablative case and the infinitive of the verb in both cases.
This is not a construction with which I am familiar to convey the same sense as the imperative mood.
As in most languages, there are lots of ways of saying the same thing. If it is for a tattoo, as some have suggested, then salute diem or vive diem might be more appropriate.
How about 'Gaudeamus in dies dies omnes nobis vivendum est'? - Let us rejoice daily (in dies - accusative plural) - then with a chiasmus arrangement - and nominative plural - every day we must live -using a gerund (vivendum est - there must be living - nobis - dative= for us)? My grammar is probably appalling. Actually - that stray nominative plural doesn't work there, does it?