


How do I use the datetime module for working with dates and times in Python?
Jun 20, 2025 am 12:58 AMPython's datetime module can meet basic date and time processing requirements. 1. You can get the current date and time through datetime.now(), or you can extract .date() and .time() respectively. 2. Can manually create specific date and time objects, such as datetime(year=2025, month=12, day=25, hour=18, minute=30). 3. Use .strftime() to output strings in format. Common codes include %Y, %m, %d, %H, %M, and %S; use strptime() to parse the string into a datetime object. 4. Use timedelta to perform date operations, such as adding and subtracting days or hours. In short, the datetime module provides the functions of obtaining, creating, formatting and calculating date and time, which is suitable for most basic scenarios.
Working with dates and times in Python is straightforward thanks to the built-in datetime
module. Whether you're logging events, scheduling tasks, or just displaying time-based information, datetime
gives you the tools you need without having to install anything extra.
Getting the Current Date and Time
The most common use of the datetime
module is probably fetching the current date and time. You can do that using datetime.now()
:
from datetime import datetime current_time = datetime.now() print(current_time)
This will output something like:
2025-04-05 13:45:30.123456
If you only need the date or the time part separately, you can extract them:
-
.date()
for just the date -
.time()
for just the time
You can also format this output if you want it in a specific string format (more on that later).
Creating Specific Dates and Times
Sometimes you don't want the current time — you might want to represent a specific moment, like an event or a birthday. For that, you can create a datetime
object manually:
from datetime import datetime event = datetime(year=2025, month=12, day=25, hour=18, minute=30) print(event)
That would give you:
2025-12-25 18:30:00
Just make sure the values ??are valid — for example, months should be between 1–12, and hours follow a 24-hour format unless you handle AM/PM manually.
You can also create date-only objects using date()
or time-only using time()
, depending on your needs.
Formatting and Parsing Dates
When showing dates to users or reading from logs/files, you often need to convert between strings and datetime
objects.
To turn a datetime
object into a nicely formatted string, use .strftime()
:
formatted = current_time.strftime("%Y-%m-%d %H:%M") print(formatted) # eg, "2025-04-05 13:45"
Here are some common formatting codes:
-
%Y
: 4-digit year -
%m
: 2-digit month -
%d
: 2-digit day -
%H
: hour (24-hour format) -
%M
: minute -
%S
: second
And if you have a string and want to parse it back into a datetime
object, use strptime()
:
date_str = "2025-04-05 13:45" parsed = datetime.strptime(date_str, "%Y-%m-%d %H:%M")
Mismatched formats will raise errors, so double-check the pattern you're using.
Doing Basic Date Math
Need to calculate how many days until a deadline? Or find out what time it was 3 hours ago?
Use the timedelta
class:
from datetime import datetime, timedelta now = datetime.now() tomorrow = now timedelta(days=1) three_hours_ago = now - timedelta(hours=3) print("Tomorrow:", tomorrow) print("Three hours ago:", three_hours_ago)
You can add or subtract timedelta
objects to/from datetime
objects to move forward or backward in time.
Some things to keep in mind:
- Arithmetic between two
datetime
objects returns atimedelta
- You can't directly multiply or divide
timedelta
objects, but you can do basic addition/subtraction
So yes, the datetime
module does cover most basic date and time needs in Python. It's not overly fancy, but once you know the core parts — getting current time, creating custom dates, formatting, and doing simple math — you'll find yourself reaching for it often.
Basically that's it.
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