Epoch Timestamp Converter

Convert Unix timestamps (seconds or milliseconds since 1970-01-01 00:00:00 UTC) to human-readable dates and vice versa. Supports multiple time zones, ISO 8601, RFC 2822, and custom formats.

Current Unix Time (UTC)
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Live Updates every second
Epoch → Date & Time
Now (1.7B)
2021-01-01
2023-01-01
2025-01-01
2025-02-19
Date & Time → Epoch
Christmas 2024
New Year 2025
Mid-2030
Privacy first: All conversions are performed locally in your browser. No data is sent to any server. Your timestamps stay on your device.

What Is a Unix Epoch Timestamp?

A Unix epoch timestamp (also known as Unix time, POSIX time, or Epoch time) is a system for describing a point in time as the number of seconds (or milliseconds) that have elapsed since January 1, 1970, 00:00:00 UTC (the Unix epoch). This simple, numeric representation of time is widely used in computing — from file systems and databases to APIs, logging, and cryptography — because it is timezone‑agnostic, easy to compare, and storage‑efficient.

Unix Timestamp = (target time in UTC) − (January 1, 1970 00:00:00 UTC)

Measured in seconds (10‑digit) or milliseconds (13‑digit). Negative values represent dates before the epoch.

Why Use an Epoch Timestamp Converter?

  • Debugging APIs & Logs: Many REST APIs and system logs use Unix timestamps. Convert them instantly to human‑readable dates for analysis.
  • Database Queries: SQL databases often store time as integer timestamps. Convert between epoch and DATETIME for reporting and data migration.
  • Cross‑Timezone Collaboration: Share a single numeric timestamp with global teams — each person can view it in their local timezone.
  • Scripting & Automation: Generate timestamps for file naming, cron jobs, or caching keys.
  • Educational Purposes: Understand how computers represent time and practice working with timezones.

How the Conversion Works

The conversion from epoch to date relies on the JavaScript Date object, which internally stores time as milliseconds since the Unix epoch. The Date constructor accepts a numeric argument (milliseconds), and we can manipulate it using toUTCString(), toISOString(), and timezone‑aware formatters like Intl.DateTimeFormat.

For date‑to‑epoch, we parse a date string and time with a specified timezone, then obtain the UTC timestamp using Date.UTC() or by constructing a Date object with the correct timezone offset. This ensures that the resulting epoch value correctly represents the selected date and time in the chosen timezone.

Our tool handles both seconds (10 digits) and milliseconds (13 digits) automatically. The "Unit" selector lets you control how the input is interpreted, preventing off‑by‑1000 errors that are common when working with timestamps.

Step‑by‑Step Usage

  1. Epoch → Date: Enter a numeric timestamp (integer or decimal), select seconds or milliseconds, choose a timezone, and click Convert to Date.
  2. Date → Epoch: Pick a date and time, choose the timezone in which the date should be interpreted, and click Convert to Timestamp.
  3. Results appear instantly in multiple formats — UTC, local, ISO 8601, RFC 2822 — all copyable with one click.
  4. Use the preset examples to quickly test common timestamps, or rely on the live clock for the current epoch.

Reference Table: Common Epoch Timestamps

All values verified against authoritative time services (time.gov, NTP pools).

Event Date (UTC) Epoch (seconds) Epoch (milliseconds)
Unix Epoch Start 1970-01-01 00:00:00 0 0
Y2K (2000-01-01) 2000-01-01 00:00:00 946684800 946684800000
2020-01-01 2020-01-01 00:00:00 1577836800 1577836800000
2038-01-19 03:14:07 2038-01-19 03:14:07 2147483647 2147483647000
2040-01-01 2040-01-01 00:00:00 2208988800 2208988800000
Case Study: Debugging an API Response

Imagine you're a backend engineer investigating a production issue. Your logs show a user session expired at timestamp 1735689600. Using this tool, you instantly see that this corresponds to 2025-01-01 00:00:00 UTC. You also check the local timezone (e.g., America/New_York) and see it was 2024-12-31 19:00:00 EST — which helps you correlate with user reports from that evening. With the ISO 8601 output, you can directly paste the value into your database query or monitoring dashboard.

The Year 2038 Problem

On January 19, 2038, at 03:14:07 UTC, the Unix timestamp will reach 2,147,483,647 — the maximum value for a signed 32‑bit integer. Systems that store timestamps in 32‑bit signed integers will overflow, wrapping to negative values (which represent dates in 1901). This is known as the Year 2038 problem (or Y2K38). Many modern systems use 64‑bit integers, which can represent dates far into the future (up to the year 292 billion). Our converter supports 64‑bit values within JavaScript's safe integer range (Number.MAX_SAFE_INTEGER ≈ 9e15), covering dates well beyond 2038.

When you enter a timestamp near 2,147,483,647, the tool will correctly display the corresponding date. You can experiment with values beyond this limit to see how 64‑bit timestamps behave — a valuable educational exercise for students and developers learning about data types and time representation.

Common Misconceptions

  • Unix time is always in UTC: Yes, the epoch itself is defined in UTC. However, the display can be in any timezone. The underlying numeric value does not change with timezone.
  • Epoch and timestamp are the same: While often used interchangeably, "epoch" specifically refers to the starting point (1970-01-01), while "timestamp" is the numeric offset from that point.
  • Leap seconds are ignored: Unix time does not account for leap seconds. It assumes exactly 86,400 seconds per day, which means it can drift slightly from astronomical time.
  • All timestamps are 10 digits: Not true — milliseconds timestamps have 13 digits, and microsecond/nanosecond timestamps are used in some systems (e.g., 16 digits). Our tool supports both seconds and milliseconds, and can be extended for other units.

Applications Across Industries

  • Software Development: Logging, session management, cache invalidation, OAuth token expiry.
  • Data Engineering: ETL pipelines, time‑series databases, event streaming (Kafka, Flink).
  • DevOps & SRE: Monitoring, alerting, and incident post‑mortems.
  • Finance: Tick data, transaction timestamps, regulatory reporting.
  • IoT & Embedded: Sensor data logging, device synchronization.

Built on open standards – This tool implements the POSIX.1-2017 specification for time and is aligned with the IETF RFC 3339 (date and time on the Internet) and RFC 2822 (email date format). The conversion logic has been tested against the official time.gov and NIST time servers. Reviewed by the GetZenQuery tech team, last updated July 2026.

Frequently Asked Questions

A seconds timestamp is a 10‑digit number (e.g., 1700000000), while a milliseconds timestamp is 13‑digit (e.g., 1700000000000). Many programming languages (JavaScript, Java, Python) use milliseconds, while others (PHP, MySQL) use seconds. Always check the expected unit before converting.

The epoch timestamp is always UTC. When you view it in your local timezone, the offset (e.g., UTC‑5 for EST, UTC+1 for CET) is applied. This is correct behavior — the same moment in time is simply represented in different timezones.

Yes. Negative values represent dates before the Unix epoch (before 1970-01-01). For example, -1 is 1969-12-31 23:59:59 UTC. The tool handles negative numbers correctly.

JavaScript's Number type is double‑precision floating point, with a safe integer range of ±9,007,199,254,740,991 (±9e15). This covers dates up to about 285,000 AD. For practical purposes, this is more than sufficient.

The timezone dropdown uses the Intl.DateTimeFormat API with the IANA timezone database (e.g., America/New_York). This ensures accurate and up‑to‑date timezone offsets, including daylight saving transitions.

For most use cases (logging, APIs, databases), precision to the second or millisecond is sufficient. For microsecond or nanosecond precision, we recommend using specialized libraries like moment.js or date-fns with extended precision.
References: RFC 3339; RFC 2822; Wikipedia: Unix Time; timeanddate.com Unix Time.