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Girish Kattel
Girish Kattel

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What Is a Unix Timestamp? How to Convert Epoch Time to Date (Python, JavaScript, Java, Node.js)

#programming #javascript #java #python

If you’ve seen numbers like 1746959680 in your code or logs and wondered what on earth is this? — welcome to the world of Unix timestamps.

In this quick guide, you’ll learn:

  • ✅ What a Unix timestamp is
  • 📅 How to convert it to a human-readable format
  • 💻 Code examples in Python, JavaScript, Java & Node.js
  • ⚡ A free tool for instant conversion → Unix Timestamp Converter

🤔 What is a Unix Timestamp?

A Unix timestamp (or Epoch time) is the number of seconds that have passed since:

📍 January 1st, 1970 at 00:00:00 UTC

This moment is known as the Unix Epoch — a standard starting point for time in computing systems.

For example:

1746959680 → May 11, 2025, 10:54:40 AM UTC
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Unix time is widely used because it’s:

  • Language-agnostic
  • Compact
  • Efficient for calculations and comparisons

🧑‍💻 Why Developers Use Unix Timestamps

Unix timestamps are everywhere for good reasons:

🔁 Easy comparisons — Just subtract two timestamps to get time differences

💽 Lightweight storage — Numbers instead of long date strings

🌐 Universal format — Used in APIs, databases, logs, and analytics

🔁 How to Convert a Unix Timestamp

✅ Use a Free Online Converter

Don’t want to write code? No problem. Paste your timestamp into a tool like:

👉 Unix Timestamp Converter)

Features:

  • Convert timestamps to UTC/local time
  • Convert both seconds and milliseconds
  • Convert from date to timestamp, and vice versa

🐍 Convert in Python

Here’s how to convert a Unix timestamp in Python:

import datetime

timestamp = 1746959680
dt = datetime.datetime.utcfromtimestamp(timestamp)
print(dt.strftime('%Y-%m-%d %H:%M:%S'))
# Output: 2025-05-11 10:54:40
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🔄 Want to skip the code? Convert it instantly with this tool

🌐 Convert in Node.js

Node.js uses the same Date object as browser JavaScript, so it’s just as simple:

const timestamp = 1746959680;
const date = new Date(timestamp * 1000);

console.log(date.toISOString());
// Output: 2025-05-11T10:54:40.000Z
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If you want local time instead:

console.log(date.toLocaleString());
// Output depends on your system’s locale and timezone
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🧠 Pro Tip: Use libraries like dayjs, luxon, or moment for more robust time formatting in Node.js apps.

🔄 Want to skip the code? Convert it instantly with this tool

🌐 Convert in JavaScript

JavaScript works with milliseconds, so multiply by 1000:

const timestamp = 1746959680;
const date = new Date(timestamp * 1000);
console.log(date.toISOString());
// Output: 2025-05-11T10:54:40.000Z
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🧠 Note: Always remember JS uses milliseconds, not seconds.

🔄 Want to skip the code? Convert it instantly with this tool

☕ Convert in Java

In Java, use the Instant and ZonedDateTime classes from the java.time package (Java 8+):

import java.time.Instant;
import java.time.ZoneId;
import java.time.ZonedDateTime;
import java.time.format.DateTimeFormatter;

public class UnixTimestampConverter {
    public static void main(String[] args) {
        long timestamp = 1746959680L;
        Instant instant = Instant.ofEpochSecond(timestamp);
        ZonedDateTime dateTime = instant.atZone(ZoneId.of("UTC"));

        String formatted = dateTime.format(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss"));
        System.out.println(formatted);
        // Output: 2025-05-11 10:54:40
    }
}
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This prints the UTC time from the Unix timestamp. You can also adjust the ZoneId for local time.

🔄 Want to skip the code? Convert it instantly with this tool

📈 Bonus: Real-World Uses

You’ll find Unix timestamps in:

🧪 Google Analytics events
🗂️ Backend logs and crash reports
🛢️ Databases like PostgreSQL and MongoDB

📎 Bookmark or Share

If this helped you understand Unix timestamps better:

⭐ Bookmark this page for later
📤 Share it with your dev team
🧭 Explore more tools at unixtimestamp-converter.com

Happy coding! 🚀

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