Date Formatting & Parsing: strftime() & strptime()

When interacting with users, databases, or APIs, dates are passed back and forth as text strings (e.g., "08-Aug-2026" or "2026/08/08 14:30:00").

Python provides two essential methods for date conversion:

1. strftime() (String Format Time): Converts a datetime object into a readable text string.
2. strptime() (String Parse Time): Converts a raw text string back into a Python datetime object.

Easy Mnemonic

• f in strftime stands for Format (Output to String).
• p in strptime stands for Parse (Input from String).

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1. Converting Dates to Strings with strftime()

from datetime import datetime

now = datetime.now()

# Format 1: Standard YYYY-MM-DD
print(now.strftime("%Y-%m-%d"))  # Output: 2026-08-08

# Format 2: Readable format (e.g. 08 August 2026)
print(now.strftime("%d %B %Y"))  # Output: 08 August 2026

# Format 3: Time format (12-hour format with AM/PM)
print(now.strftime("%I:%M %p"))  # Output: 01:45 PM

# Format 4: Complete timestamp with weekday
print(now.strftime("%A, %b %d, %Y - %H:%M:%S"))
# Output: Saturday, Aug 08, 2026 - 13:45:10

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2. Essential Format Codes Cheatsheet

Code	Meaning	Example Output
%Y	4-Digit Year	2026
%y	2-Digit Short Year	26
%m	2-Digit Month Number	08
%B	Full Month Name	August
%b	Short Month Name	Aug
%d	Day of Month (01-31)	08
%A	Full Weekday Name	Saturday
%a	Short Weekday Name	Sat
%H	24-Hour Clock (00-23)	14
%I	12-Hour Clock (01-12)	02
%M	Minutes (00-59)	30
%S	Seconds (00-59)	45
%p	AM / PM marker	PM

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3. Parsing Raw Text into Dates with strptime()

When receiving raw date strings from API JSON payloads or user input forms, use strptime() with the exact matching format template:

from datetime import datetime

raw_input_1 = "25/12/2026"
date_obj_1 = datetime.strptime(raw_input_1, "%d/%m/%Y")
print("Parsed Date:", date_obj_1.year)  # Output: Parsed Date: 2026

raw_input_2 = "2026-Aug-15 09:30 AM"
date_obj_2 = datetime.strptime(raw_input_2, "%Y-%b-%d %I:%M %p")
print("Parsed Month:", date_obj_2.month)  # Output: Parsed Month: 8

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Quick Summary

• strftime(format) (String From Time): Converts datetime objects into formatted custom text strings (e.g., %Y-%m-%d).
• strptime(str, format) (String Parse Time): Parses raw strings from APIs or forms into Python datetime objects.
• Core Format Codes: %Y (4-digit year), %m (month number), %B (month name), %d (day), %H (24h) / %I (12h), %M (minute), %p (AM/PM).

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What's Next?

Let's look at hardware timers, rate-limiting delays, and precision performance benchmarking with the time module!