Bulk Unix Timestamp Converter
Paste a whole column of epoch values and convert them together, rather than one at a time. This page opens in batch mode.
The typical source is a log extract or a query result where the timestamps are unreadable and you need the whole set in context.
Reading a sequence rather than a point
Converting in bulk is what makes gaps and clusters visible. A run of events every few seconds followed by a four-minute hole is obvious as a list of times and invisible as a list of ten-digit integers.
Because the whole set converts under one unit assumption, a value that lands wildly out of line usually means that row is in a different unit - worth knowing before you draw conclusions from it.
Keeping the data local
A column of timestamps pasted out of production logs often arrives with identifiers and paths attached. Everything here is converted in the browser, so a bulk paste does not become an upload.
Mixed units in one column
Systems that changed their logging at some point produce columns with both seconds and milliseconds in them. Detection is per value by magnitude, so a mixed column still converts sensibly, but it is worth checking the boundary rows to confirm the split is where you expect.
Sorting before converting
Epoch values sort correctly as numbers but not as strings, and a column pasted from a spreadsheet is text. Sorting lexicographically puts a 13-digit millisecond value before a 10-digit second value regardless of the instant.
Convert first, then sort by the resulting date, or sort numerically before pasting.