Timestamp Converter | TechToolkit

Q: What is the Unix epoch?

The Unix epoch is January 1, 1970, at 00:00:00 UTC. A Unix timestamp is the number of seconds (or milliseconds) elapsed since that moment. It is timezone-agnostic, making it ideal for storing and comparing times in databases and APIs.

Q: What is the difference between seconds and milliseconds timestamps?

Unix timestamps in seconds are the classic format. JavaScript's Date.now() returns milliseconds (seconds × 1000). A 10-digit number is likely seconds, while a 13-digit number is milliseconds.

Timestamp Converter

Convert Unix timestamps to human-readable dates and back. Supports milliseconds, multiple timezones, ISO 8601, and relative time output.

Unix → Human Date Date → Unix Milliseconds Support Timezone-Aware ISO 8601 Relative Time

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Timestamp Formats Reference

Every common timestamp format with examples and context on where each is used.

Format	Example	Notes
Unix Seconds	1719792000	Seconds since 1970-01-01T00:00:00Z. Used in most backend systems.
Unix Milliseconds	1719792000000	Milliseconds since epoch. Default in JavaScript Date.now().
ISO 8601	2024-06-30T16:00:00Z	International standard. The Z indicates UTC.
RFC 2822	Sun, 30 Jun 2024 16:00:00 +0000	Used in email headers (Date: field).
HTTP Date	Sun, 30 Jun 2024 16:00:00 GMT	Used in HTTP headers (Last-Modified, Expires).
Human Local	June 30, 2024 at 4:00 PM	Locale-specific display format.

Frequently Asked Questions

What is the Unix epoch?

The Unix epoch is the point in time from which Unix timestamps are measured: January 1, 1970, at 00:00:00 UTC. A Unix timestamp is simply the number of seconds (or milliseconds) that have elapsed since that moment. It is timezone-agnostic — the same integer represents the same instant in time worldwide, which makes it ideal for storing and comparing times in databases and APIs.

What is the difference between seconds and milliseconds timestamps?

Unix timestamps in seconds are the classic format used by most server-side languages and databases. JavaScript's Date.now() and many browser APIs return milliseconds (seconds × 1000). A quick way to tell them apart: a 10-digit number is likely seconds (valid until year 2286), while a 13-digit number is milliseconds. Dividing or multiplying by 1000 converts between them.

What is the Y2K38 problem?

The Y2K38 problem will occur on January 19, 2038, at 03:14:07 UTC. At that moment, a signed 32-bit integer used to store Unix timestamps will overflow and wrap to a large negative number, causing dates to appear as December 13, 1901. Systems using 64-bit integers are not affected, and most modern systems have already been updated.

What is the ISO 8601 date format?

ISO 8601 is an international standard for representing dates and times. The full format is YYYY-MM-DDTHH:mm:ss±HH:mm (e.g., 2024-06-30T16:00:00+02:00). The T separates the date and time, and the trailing Z or offset indicates the timezone. ISO 8601 is unambiguous, sortable as a string, and recommended for all APIs and data interchange.

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Convert Any Timestamp Instantly

Decode cryptic Unix timestamps into human-readable dates across any timezone, in seconds.

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