Thu, Mar 05, 2026 12:41:45 UTC

Cocoa Timestamp Converter

Convert Apple NSDate and Core Data timestamps to human-readable dates

What is a Cocoa Timestamp?

Cocoa timestamps count seconds since January 1, 2001 00:00:00 UTC. This is the reference date used by Apple's NSDate class in Objective-C and Swift's Date type. These timestamps appear in Core Data databases, property lists, and throughout macOS and iOS application data.

Where You'll Encounter Cocoa Timestamps

Core Data SQLite databases store date attributes using this format. macOS system logs, iOS app databases, iCloud sync timestamps, and backup metadata all use Cocoa timestamps. When developing iOS or macOS apps with Swift or Objective-C, NSDate.timeIntervalSinceReferenceDate returns this format.

How to Convert

Paste any Cocoa timestamp into the converter above. Chronoshift detects the format based on the value range and converts it to human-readable dates, Unix timestamps, and ISO 8601 format with copy buttons.