Why do I get different timestamps in python on different machines?

A timestamp represents a specific point in time as a numerical value. It typically measures the number of seconds that have elapsed since the Unix epoch, which is January 1, 1970, at 00:00:00 Coordinated Universal Time (UTC).

The main reasons behind timestamp variations on different machines include differences in time zones, system clocks, locale settings, and the use of UTC and local time (such as IST, PST, or CET). In this article, we will explore timestamp differences across different machines by considering the following key factors.

Different System Time Zones

If each system were set to different time zones like IST (Indian Standard Time), PST (Pacific Standard Time) or UTC (Coordinated Universal Time) would lead to variations in timestamps. Let's assume there are two systems, A and B. If System A is in India (IST) and Machine B is in the US (PST), their timestamps will be different.

Example

In general, we will use datetime.now() method to return the current date and time based on the local timezone of the system. The following program will return different timestamps depending on where the machine is located.

To avoid getting different timestamps, we can use the datetime.now(timezone.utc) method instead of the datetime.now()

from datetime import datetime

print("Local time:", datetime.now())

Local time: 2025-06-17 14:30:00.123456

Local time: 2025-06-17 01:00:00.123456

Unsynchronised System Clocks

Even if two systems are in the same timezone, but internal system clocks are not synchronised perfectly will also lead to a difference in timestamp. If one system is ahead or behind by a few seconds or minutes, it will show how the system clock was accurate or outdated.

Example

Here, we used the previous code to demonstrate the differences in timestamps that occurred due to unsynchronised system clocks of the two systems.

from datetime import datetime

print("System time:", datetime.now())

System time: 2025-06-17 14:32:00

System time: 2025-06-17 14:30:00

Varying Locale Settings

The term locale defines how a timestamp is formatted and displayed, including language, date order, and symbols. This will not change the actual time value, but it affects how the timestamp looks when converted to a string. Setting the locale to standard formats like ISO 8601 for displaying dates will avoid ambiguity.

Example

In the following program,  locale.setlocale() function from the locale module sets two different locale settings (US English and French) and retrieves the current datetime using datetime.now(). The strftime("%c") gives the locale's preferred date and time.

import locale
from datetime import datetime

# US English
locale.setlocale(locale.LC_TIME, 'en_US.UTF-8')
print("US Format:", datetime.now().strftime("%c"))

# French
locale.setlocale(locale.LC_TIME, 'fr_FR.UTF-8')
print("French Format:", datetime.now().strftime("%c"))

Following is the output for the above code:

US Format: Tue Jun 17 14:30:00 2025
French Format: mar. 17 juin 2025 14:30:00