Apple Cocoa timestamp to date converter
iOS and macOS apps store dates as seconds since the start of 2001, and some databases such as Messages use nanoseconds. Enter a value to read it.
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How to use it
- Enter cocoa timestamp, unit and time zone (optional).
- The result appears straight away and updates as you edit.
- Copy the result, or copy a link that keeps the same values to share it.
How it is calculated
Unix seconds = Cocoa timestamp + 978307200, the Unix time of 2001-01-01 00:00:00 UTC. Nanosecond values are divided by 1000000000 first.
Example
Inputs: Cocoa timestamp = 812505600, Unit = Seconds (NSDate, Core Data), Time zone (optional) = Riyadh (Saudi Arabia). Result: Date and time (UTC): 2026-10-01 00:00:00; Weekday: Thursday.
812505600
2026-10-01 00:00:00
Limits and caveats
- Check the unit: current values are about 9 digits in seconds and 18 digits in nanoseconds.
- A Cocoa timestamp is always UTC.
Questions about this tool
What is a Cocoa timestamp?
It is Apple's timeIntervalSinceReferenceDate, seconds since 1 January 2001 UTC, also called Mac absolute time.
Why is my date 31 years off?
Reading a Cocoa value as Unix time gives a date near 1995 instead of 2026. This converter adds the 978307200-second offset.
Where do nanosecond values appear?
In the Messages chat.db database on recent systems, where the date field has 18 digits.