2100 at a glance
- 12-hour time
- 9:00 PM
- 24-hour clock
- 21:00
- Say it
- twenty-one hundred hours
- Part of day
- Night
- Minutes after midnight
- 1,260
- Minutes until midnight
- 180
- Decimal hours
- 21.00
- Share of the day gone
- 87.5%
How to convert 2100 to standard time
- The hour digits are 21, which is past noon. Subtract 12 from the hour: 21 − 12 = 9.
- Keep the minutes (00), insert a colon and add PM: 9:00 PM.
How to say 2100
| Style | How it sounds |
|---|---|
| Military (spoken) | “twenty-one hundred hours” |
| Short form | “twenty-one hundred” |
| Radio, digit by digit | “two one zero zero” |
| Civilian | “nine o’clock at night” |
| Written 24-hour | 21:00 or 2100 |
On the hour, the minutes are spoken as “hundred”: 2100 is “twenty-one hundred hours.”
2100 Zulu (UTC) in US time zones
Military and aviation schedules give times in Zulu — Coordinated Universal Time — so that everyone works from one clock. When a message says 2100Z, this is the local time across the United States:
| Time zone | Standard time | Daylight time |
|---|---|---|
| Eastern (EST / EDT) | 4:00 PM — R | 5:00 PM — Q |
| Central (CST / CDT) | 3:00 PM — S | 4:00 PM — R |
| Mountain (MST / MDT) | 2:00 PM — T | 3:00 PM — S |
| Pacific (PST / PDT) | 1:00 PM — U | 2:00 PM — T |
| Alaska (AKST / AKDT) | 12:00 PM — V | 1:00 PM — U |
| Hawaii (HST) | 11:00 AM — W | No daylight time |
The letter after each time is that zone’s military time-zone letter: Eastern standard time is R (Romeo, UTC−5), so 2100Z is 1600R. Daylight time runs from the second Sunday in March to the first Sunday in November; Hawaii and most of Arizona stay on standard time all year.
If 2100 is your local time
- 2100 Eastern is 0200Z in winter (EST) and 0100Z in summer (EDT).
- 2100 Central is 0300Z in winter (CST) and 0200Z in summer (CDT).
- 2100 Mountain is 0400Z in winter (MST) and 0300Z in summer (MDT).
- 2100 Pacific is 0500Z in winter (PST) and 0400Z in summer (PDT).
Times around 2100
| Change | Military | Standard |
|---|---|---|
| −60 min | 2000 | 8:00 PM |
| −45 min | 2015 | 8:15 PM |
| −30 min | 2030 | 8:30 PM |
| −15 min | 2045 | 8:45 PM |
| This time | 2100 | 9:00 PM |
| +15 min | 2115 | 9:15 PM |
| +30 min | 2130 | 9:30 PM |
| +45 min | 2145 | 9:45 PM |
| +60 min | 2200 | 10:00 PM |
Shifts that start at 2100
- An 8-hour shift starting at 2100 ends at 0500 (5:00 AM the next day).
- A 10-hour shift starting at 2100 ends at 0700 (7:00 AM the next day).
- A 12-hour shift starting at 2100 ends at 0900 (9:00 AM the next day).
- To total the hours on a real time card with breaks, use the time card calculator.
2100 in everyday use
- 2100 is late evening — 9:00 PM. Quiet hours at many campgrounds, hotels and apartment buildings start around 2200, and night-shift handovers often happen in this window.
- For 2000 to 2359, subtract 12 from the whole hour: 21 − 12 = 9, so 2100 is 9:00 PM. The day ends 180 minutes later, when the clock rolls over to 0000.
Frequently asked questions
What is 2100 in regular time?
2100 is 9:00 PM in regular 12-hour time. Subtract 12 from the hour (21 − 12 = 9) and add PM.
Is 2100 AM or PM?
2100 is PM. Military times from 0000 to 1159 are AM and times from 1200 to 2359 are PM.
How do you say 2100 in military time?
Say “twenty-one hundred hours.” In radio procedure each digit is spoken separately, so 2100 can also be read digit by digit.
What is 2100 Zulu in Eastern time?
2100Z is 4:00 PM Eastern Standard Time (UTC−5) and 5:00 PM Eastern Daylight Time (UTC−4).