54321 (disambiguation)

54321 may refer to:

• 54321, a 2016 Tamil-language film
• "54321" (song), a 2022 song by Offset
• "5-4-3-2-1", a song by Manfred Mann
• 5-4-3 rule or 5-4-3-2-1 rule, an Ethernet design guideline
• Countdown, a sequence of backward counting towards a scheduled event