Time Conversion Chart for Nurses
Updated June 20, 2026
Hospitals run on 24-hour time to prevent dangerous AM/PM mix-ups. To convert any 24-hour time, subtract 12 from hours 13 through 23 and add PM. This guide gives you a printable quick reference chart, common nursing shift times, and medication pass schedules. Everything you need to switch between the two formats fast.
Why 24-hour time matters in nursing
Writing "2:00" on a MAR or order creates a 50% chance of confusion. Is it AM or PM? 24-hour time removes the ambiguity: 02:00 is always 2 AM, 14:00 is always 2 PM. This is why the Joint Commission, WHO, and ISMP all recommend 24-hour time for medication documentation. Use the converter to double-check any time.
Printable pocket chart: 24-hour to 12-hour
Print this table and keep it in your pocket or on your badge. Covers every hour of the day.
| 24-hour | 12-hour | Nursing context | 24-hour | 12-hour | Nursing context |
|---|---|---|---|---|---|
| 00:00 | 12:00 AM | Midnight — shift start | 12:00 | 12:00 PM | Noon med pass |
| 01:00 | 1:00 AM | Overnight vitals | 13:00 | 1:00 PM | Post-lunch checks |
| 02:00 | 2:00 AM | Overnight rounds | 14:00 | 2:00 PM | Afternoon med pass |
| 03:00 | 3:00 AM | Overnight checks | 15:00 | 3:00 PM | Day shift wrap-up |
| 04:00 | 4:00 AM | Early labs | 16:00 | 4:00 PM | Evening shift start |
| 05:00 | 5:00 AM | Pre-breakfast vitals | 17:00 | 5:00 PM | Dinner med pass |
| 06:00 | 6:00 AM | Day shift report | 18:00 | 6:00 PM | Evening vitals |
| 07:00 | 7:00 AM | Shift change | 19:00 | 7:00 PM | Night shift report |
| 08:00 | 8:00 AM | Morning med pass | 20:00 | 8:00 PM | Evening med pass |
| 09:00 | 9:00 AM | Doctor rounds | 21:00 | 9:00 PM | HS medications |
| 10:00 | 10:00 AM | Late morning checks | 22:00 | 10:00 PM | Bedtime med pass |
| 11:00 | 11:00 AM | Pre-noon prep | 23:00 | 11:00 PM | Overnight shift start |
For every time at 15-minute intervals, see the full time conversion chart.
Standard medication pass times
Most hospital units follow a four-pass schedule. The exact times vary by facility, but this is the most common setup:
| Pass name | 24-hour time | 12-hour time | What it covers |
|---|---|---|---|
| Morning | 08:00 | 8:00 AM | Daily maintenance meds, antibiotics, insulin |
| Noon | 12:00 | 12:00 PM | Midday antibiotics, pain medications |
| Afternoon | 17:00 | 5:00 PM | Evening antibiotics, daily meds, pre-dinner insulin |
| Bedtime (HS) | 22:00 | 10:00 PM | Sleep aids, overnight pain meds, last daily dose |
Some units add an early morning pass at 06:00 (6 AM) for pre-breakfast insulin or thyroid meds, and a mid-afternoon pass at 14:00 (2 PM) for post-op or ICU units.
Common nursing shifts in 24-hour format
Day shift
07:00 – 19:00 (7 AM – 7 PM)
Twelve hours. Most common shift in US hospitals.
Night shift
19:00 – 07:00 (7 PM – 7 AM)
Overnight. Covers midnight vitals and early morning labs.
Evening shift (3-11)
15:00 – 23:00 (3 PM – 11 PM)
Eight hours. Common in facilities that use 3-shift rotation.
Morning shift (7-3)
07:00 – 15:00 (7 AM – 3 PM)
Eight-hour day shift. Still used in some teaching hospitals.
How to convert quickly in your head
After a few shifts, the conversion becomes second nature. Here is the fast mental method most nurses use:
For PM times (13:00–23:59): Subtract 2 from the hour, then drop the first digit. 14:00 → 14 − 2 = 12 → drop the 1 → 2:00 PM. 17:00 → 17 − 2 = 15 → drop the 1 → 5:00 PM. Works because 13 − 2 = 11 + 1 = 12... the easy trick: subtract 12. Same thing.
For AM times (00:00–11:59): Just remove the leading zero and add AM. 07:00 = 7:00 AM. One exception: 00:00 is 12:00 AM (midnight).
Noon: 12:00 is 12:00 PM. This one trips people up because it looks like it should be AM. Remember: 12:00 in 24-hour time is always noon, never midnight.
Practice reference: 13:00 = 1 PM, 14:00 = 2 PM, 15:00 = 3 PM, 16:00 = 4 PM, 17:00 = 5 PM, 18:00 = 6 PM, 19:00 = 7 PM, 20:00 = 8 PM, 21:00 = 9 PM, 22:00 = 10 PM, 23:00 = 11 PM.
Documentation tips for nursing students
- Always use four digits. Write 08:00, not 8:00. The leading zero matters in medical records.
- Midnight is 00:00, not 24:00. Most EHR systems and MARs use 0000 for midnight entries.
- Use the colon in narrative notes (08:00), drop it in flow sheets (0800). Both are correct; check your facility's policy.
- Double-check the 12's. 12:00 = noon, 00:00 = midnight. This is the #1 error in nursing documentation.
- Be consistent. If your unit uses 24-hour time in the MAR, use it in your notes too. Mixing formats creates confusion.