Unix Timestamp and Epoch in Go

Unix time counts elapsed time from the Unix epoch at 1970-01-01T00:00:00Z. Different ecosystems use different units, so always label whether a value is in seconds, milliseconds, microseconds, or nanoseconds.

Quick Start#

The following example uses the standard Go API or a widely used package for this task.

Quick start#

1now := time.Now().UTC()2seconds := now.Unix()3milliseconds := now.UnixMilli()4fmt.Println(seconds, milliseconds)

Common Operations#

This second pattern covers a common production operation or a safer way to handle real input.

Convert back#

1fromSeconds := time.Unix(epochSeconds, ).UTC()2fromMilliseconds := time.UnixMilli(epochMilliseconds).UTC()3fmt.Println(fromSeconds.Format(time.RFC3339Nano))

Important Notes#

Go time.Time carries location information for formatting; normalize to UTC when serializing cross-system timestamps unless a named timezone is part of the domain.

Best Practices#

1. Treat external input as untrusted and handle parse/validation errors explicitly.
2. Keep encoding, units, formats, and library-specific mapping rules explicit at system boundaries.
3. Add test vectors that cover empty input, Unicode text, malformed input, and representative production data.

References#

• POSIX Seconds Since the Epoch
• Go Standard Library