Python String Slicing Explained Visually

Indexing Basics

s = "PyForm"
# P y F o r m
# 0 1 2 3 4 5
print(s[0])   # P
print(s[-1])  # m (negative indexes count from the end)

Slicing Syntax

s[start:stop:step]

The stop index is exclusive. Omitted values default to start=0, stop=len(s), step=1.

s = "PyForm"
print(s[0:2])    # Py
print(s[2:])     # Form
print(s[:4])     # PyFo
print(s[::2])    # PFr
print(s[::-1])   # mroFyP (reverse)

Common Patterns

• First 3 chars: s[:3]
• Last 3 chars: s[-3:]
• Drop first char: s[1:]
• Drop last char: s[:-1]
• Reverse: s[::-1]

Slicing Works on Lists Too

nums = [10, 20, 30, 40, 50]
print(nums[1:4])   # [20, 30, 40]
print(nums[::-1])  # [50, 40, 30, 20, 10]