Today

Kanji words often have more than one reading. The choice depends on context—casual, polite, or formal. Japanese uses both on-yomi (Chinese-derived) and kun-yomi (native).

今日きょう — the most common reading: “today.”
今日こんにち — a more formal reading: “nowadays,” “these days.”

Tomorrow

明日あした — the most common, casual way: “tomorrow.”
明日あす — a bit more formal, often used in writing or speeches.
明日みょうにち — formal or traditional, seen in announcements, schedules, or classical contexts.

Tip: This is one reason why Japanese often has several readings for the same word. Don’t worry about memorizing them all at once. Start with the most common ones: きょう for 今日 and あした for 明日. You’ll naturally come across the other readings in news, books, and formal settings.