Unix timestamp converter
Unix time counts seconds since 1970-01-01 00:00:00 UTC (milliseconds in JavaScript Date.now()). Logs, JWT exp, and API fields often use epoch numbers — convert to readable local or UTC datetime for debugging incidents.
Unix timestamp
ISO
2026-08-12T19:34:17.000Z
ISO
Unix timestamp
1786563257
How to convert timestamps
1. Paste epoch number or pick datetime from picker.
2. Toggle seconds vs milliseconds if value looks wrong (10 vs 13 digits).
3. Read UTC and local timezone results.
4. Copy converted value for SQL query or log filter.
Timestamp examples
JWT exp claim
1735689600 decodes to future expiry — compare with now.
JavaScript Date.now()
1704067200000 ms equals 2024-01-01 UTC — 13-digit values are ms.
Log line parse
Convert nginx $msec or epoch field to correlate with Splunk human time.
When to convert epochs
• When debugging API responses with numeric dates.
• When writing database queries with UNIX_TIMESTAMP().
• When onboarding learns UTC vs local display.
Ambiguity traps
• When timestamp is microseconds or nanoseconds — scale differs (16+ digits).
• When date string already ISO8601 — parse directly in code.
• When leap seconds matter — Unix time ignores leap second labeling quirks.
Always confirm unit
Mixing seconds where ms expected offsets dates by 1000× — common bug in mobile analytics SDKs.
Daylight saving
Local wall clock jumps — epoch is continuous. Schedule cron in UTC to avoid DST bugs.
Database storage
Store UTC instants as TIMESTAMP WITH TIME ZONE; convert at UI layer for users.
Frequently asked questions
Seconds or milliseconds?
10-digit ≈ seconds; 13-digit ≈ milliseconds until year 2286.
UTC vs local?
Epoch is UTC instant — display may show local timezone offset.
Negative timestamps?
Pre-1970 dates possible in some systems — rare in web APIs.
Y2K38 problem?
32-bit signed int overflows 2038 — use 64-bit long in systems.
Local?
Yes.
ISO output format?
Often 2024-03-15T14:30:00.000Z — copy for JSON APIs.