Unix timestamp converter
Turn a numeric timestamp into a readable date. Compare Korea Standard Time and UTC side by side.
Convert log timestamps
Paste a log line or a timestamp string; the format is detected and converted to UTC, Korea time and your browser’s time zone.
Input is processed in your browser and is not sent to the server.
Quick start
- Enter a timestamp or date.
- Choose the input unit. Automatic detection uses the size of the value and may differ from the original unit.
- Compare KST and UTC.
Unix time and time zones
A Unix timestamp counts time from 1970-01-01 00:00:00 UTC. KST is UTC+09:00. The date input on this page is explicitly Korean time, regardless of the interface language or your browser’s time zone.
Automatic unit estimation
| Absolute input value | Interpreted as |
|---|---|
| Below 10^11 | Seconds |
| 10^11 to below 10^14 | Milliseconds |
| 10^14 or greater | Microseconds, rounded down to milliseconds |
Check the unit for distant dates
These thresholds suit present-day timestamps. They can misclassify dates far in the past or future. Check the source unit and displayed result before using it.
JavaScript Date has a finite range and millisecond precision. This tool is not a high-precision or leap-second timescale converter. Processing runs in your browser.
Input unit
Choose the input unit. Automatic detection uses the size of the value and may differ from the original unit.
Aligning server log timestamps
The same moment is written differently in different logs. Formats that include a time zone convert directly; for formats without one, check the server’s time zone setting before choosing the assumption. When comparing logs from several servers, converting everything to UTC makes the order clear.
| Format | Example | Time zone information |
|---|---|---|
| Nginx/Apache access log | [12/Oct/2026:10:15:32 +0900] | Included (+0900) |
| Nginx error log | 2026/10/12 10:15:32 | None · server time zone |
| ISO 8601 · journalctl -o short-iso | 2026-10-12T10:15:32+09:00 | Included |
| syslog · journalctl default output | Oct 12 10:15:32 | None · no year either |
| HTTP Date header | Mon, 12 Oct 2026 01:15:32 GMT | Included (GMT) |
The PPORT production server (OCI, Ubuntu) uses UTC as its system time zone, so its Nginx error log and default journalctl output are also in UTC. When comparing them with logs from a server or PC that records Korea time, account for the nine-hour difference first. Check a server’s setting with the commands below.
timedatectl | grep 'Time zone'
date -u +%FT%TZ
journalctl -u nginx --since '2026-10-12 01:00' --utc -o short-isoGet-TimeZone | Select-Object Id,BaseUtcOffset
(Get-Date).ToUniversalTime().ToString('o') Time zone: Etc/UTC (UTC, +0000)
2026-10-12T01:15:32Z