We are soon opening a website and want to say that it's coming soon. I've found "kommt bald" or "demnächst" - which one should I use?
To be honest, I have never seen a short equivalent translation for "coming soon" on Websites in German. I am even used to read an information of this kind in English.
Nevertheless, one would understand your suggestion with "kommt bald".
"Demnächst" you couldn't leave alone without a context. Generally, trying to translate "coming soon" into German, I would suggest even short sentences.
Following suggestions came to my mind:
Diese Website ist schon bald für Sie erreichbar.
Diese Website ist demnächst für Sie erreichbar.
"Kommt bald" can be used, but in my opinion, it sounds a bit dull (german: stumpf). If you use "demnächst", you would have to connect it to another word. "Kommt demnächst" oder "demnächst verfügbar" would be possible translations. Another possibility would be "in Bearbeitung", though it isn't an exact translation of "coming soon". (rather "under construction")
"In Kürze" would be the most fitting expression for what you described. But in Germany we wouldnt use that. For a page thats about to or is being build at the moment we would go with "Im Aufbau" or more explicit: "Seite im Aufbau" "Website im Aufbau" would also fit, caus we actually use a lot of english terms in daily situations (unlike the french). "Seite kommt in Kürze" also.