Converter
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24‑hour
—
12‑hour
—
Notes
Awaiting input…
Results Table
| # | Input | Direction | From | To | 24‑hour | 12‑hour | Day shift | Notes | Actions |
|---|
Example Data
Click a row to load it into the form, then convert and add it to the table.
| Direction | Time input | From | To | Assume seconds |
|---|---|---|---|---|
| 24‑hour → 12‑hour | 0000 | UTC+0 | UTC+5:30 | 00 |
| 24‑hour → 12‑hour | 23:59:59 | UTC+0 | UTC−5 | 00 |
| 12‑hour → 24‑hour | 12:00 AM | UTC+5:45 | UTC+0 | 00 |
| 12‑hour → 24‑hour | 11:15:30 PM | UTC−4 | UTC+9 | 00 |
| 24‑hour → 12‑hour | 07:45 | UTC+10:30 | UTC+10:30 | 30 |
How to Use
- Select the conversion Direction.
- Enter a value in Time input. Examples: 2315, 23:15, 23:15:45 or 11:15 PM.
- Pick From offset and To offset for optional time‑zone conversion.
- Click Convert to preview. Use Add to table to save the row.
- Export your work using Download CSV or Download PDF.
Validation guides your input. The calculator labels day shifts if the target offset crosses midnight.
Formulas Used
24‑hour → 12‑hour: Let H be hours (0–23), M minutes, S seconds.
- Period: AM if H < 12, else PM.
- Hour: h12 = ((H + 11) mod 12) + 1 so 00 → 12, 13 → 1.
- Format: h12:MM[:SS] AM/PM.
12‑hour → 24‑hour: Let h be 1–12, period P ∈ {AM, PM}.
- If P = AM: H = (h == 12) ? 0 : h.
- If P = PM: H = (h == 12) ? 12 : h + 12.
- Format: HH:MM[:SS], with leading zeros.
Offset conversion: Let Δ = offsetTo − offsetFrom in minutes. Then t' = t + Δ, where t is minutes since midnight. Day shift is noted if t' wraps.
FAQs
Enter compact military values like 0000 or 2315, separated formats like 23:15 or 23:15:45, or 12‑hour strings like 11:15 PM.
If seconds are missing, the calculator uses your chosen default seconds. Invalid patterns trigger guidance so you can correct formatting quickly.
Yes. Select source and target offsets. The tool adjusts minutes and flags if the result crosses into the previous or next day.
Use Download CSV for spreadsheets or Download PDF for printable reporting. Only the results table is exported.
Yes. 00:00 equals 12:00 AM and 12:00 equals 12:00 PM. The formulas above ensure correct handling.