Convert Slack Unix timestamps into readable dates and times. Supports UTC, local timezone, relative time, and Slack date syntax generation.
The `ts` field in Slack API and webhook responses isn't a human-readable date: it's a Unix timestamp, the number of seconds since midnight UTC on January 1, 1970. A message object might show `"ts": "1718071200.123456"`, with microsecond precision after the decimal point. Servers, logs, and APIs pass this format around because it needs no timezone notation, but you can't read it at a glance when you're staring at a log or debugging.
Paste a raw timestamp like that into this converter and it shows UTC, your local time, and relative time (like "3 hours ago") side by side, so you can immediately tell what a logged moment actually was.
When you announce a meeting or deploy time to a team spread across timezones, writing a fixed "3 PM" invites confusion about whose 3 PM you mean. Slack's `<!date^...>` syntax solves this differently: embed a Unix timestamp and a display format in the message, and Slack re-renders it in each reader's own local timezone automatically.
This tool pre-builds the same instant in commonly used formats, like `{date_short_pretty} at {time}` and `{date_long_pretty} at {time_secs}`, so you can copy whichever one you need straight into your message.
Unix timestamps in seconds, milliseconds, and microseconds look like similar numbers at a glance and are easy to mix up (10 digits vs. 13 vs. 16). This tool reads the digit count and tells the three apart automatically, and it also recognizes plain date-time strings like ISO 8601 or an already-built `<!date^...>` Slack syntax pasted back in.
That means you can paste a syntax already embedded in a Slack message to check exactly what moment it originally referred to.
Logging a Slack API response shows the ts field in this shape. The digits after the decimal are sub-second precision, and pasting the value as-is is recognized automatically.
Paste this into a message and a colleague in New York sees New York time while one in Seoul sees Seoul time, each rendered locally.
JavaScript's Date.now() returns milliseconds while most server logs use seconds. You don't have to count digits yourself; the tool tells them apart and lands on the same result.
What it is, who it's for, how it works and why you'd use it.
A Slack Timestamp Converter converts Unix timestamps used by Slack into human-readable dates and times, and generates Slack's <!date> syntax.
It is for developers working with the Slack API and webhooks, and for PMs announcing times to teams across timezones.
Enter a timestamp or date and the format is auto-detected, then converted to UTC, your local time, relative time and Slack date syntax all at once.
It prevents timezone mistakes and produces Slack syntax that renders in each reader's own timezone with a single click.