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Convert timestamps to time zones and export batches to CSV

A timestamp identifies an instant; a time zone determines how that instant is displayed. Two locations can show different dates or clock times for the same event.

UTC and explicit offsets

The inputs 2024-01-01T00:00:00Z and 2024-01-01T01:00:00+01:00 identify the same instant: Unix second 1704067200. Z means UTC. The +01:00 offset means the written local clock is one hour ahead of UTC, so subtract one hour to get UTC.

Why local dates need an offset

A local time such as 2024-11-03T01:30:00 is ambiguous in New York when clocks move back. With -04:00 it identifies 05:30 UTC; with -05:00 it identifies 06:30 UTC. Epochdesk requires Z or a numeric offset in ISO input instead of silently choosing one interpretation.

A numeric offset is not a named time zone. Europe/Paris has seasonal rules; +01:00 describes only a fixed offset. For output, choose the named zone appropriate to the event. Your browser provides the time-zone rules used for display.

Convert a batch

  1. Paste one timestamp or ISO date per line into the converter.
  2. Select an explicit unit if all numeric rows use the same unit. Auto mode can handle contemporary mixed units.
  3. Choose the output time zone and select Convert timestamps.
  4. Review invalid rows. The summary displays the first valid result, while the table retains every nonblank input row.
  5. Select Export CSV to download UTC, selected-zone dates and numeric timestamp columns.

Try these inputs

1704067200
1704067200000
1704067200000000
2024-01-01T01:00:00+01:00

In auto mode these four rows identify the same instant. The converter accepts up to 5,000 nonblank lines per batch. Paste values only; it does not parse an uploaded CSV file or split comma-separated columns.

Preserve precision in spreadsheets

Spreadsheet software can reformat dates or round long numeric values. Import precise timestamp columns as text and keep the original file. Epochdesk quotes CSV fields and prefixes values beginning with certain formula characters with an apostrophe, including negative inputs, to reduce spreadsheet formula interpretation. Account for that prefix if you later re-import the exported text.

Where does my data go?

Conversions and CSV generation run in your browser. The converter does not send your input to a conversion API. Hosting still involves ordinary web requests; see the privacy page for details.

Practical timestamp guides