Translation guide
In Japanese, 'this day' is rarely translated literally. The most natural equivalent depends on whether you mean 'today', 'this very day' (emphatic), or 'this day' in a narrative or formal context.
The speaker refers to the current calendar day in a neutral, everyday context.
The standard word for 'today'. Use this in almost all everyday situations.
今日はいい天気ですね。
It's nice weather today, isn't it?
What are your plans for today?
A formal equivalent of 'today', used in business, announcements, and written contexts.
Thank you for coming today.
The speaker emphasizes that something happens on this specific day, often with a sense of importance or immediacy.
Literally 'this day', used to emphasize a particular day, often in narratives or when referring to a significant day.
I've been waiting for this day for a long time.
This day has finally come.
Emphasizes 'this very day called today', often used in reflective or poetic contexts.
I won't forget this day.
The speaker refers to a specific day in a narrative, often not the present day.
Directly translating 'this day' as この日 (kono hi) in everyday conversation about today sounds unnatural. Use 今日 (kyō) for 'today' unless you specifically want to emphasize the day in a narrative or emotional way.
そして、その日がやってきた。
And then, this day arrived.