Use Python’s str.rfind() to get the index of a substring’s final occurrence. It returns the highest matching index, or -1 if there is no match. Use str.rindex() instead if a missing match should raise ValueError.
Find the final match with rfind()
Call rfind(sub) on the string you want to search. The returned value is the zero-based index where the final match begins—not the number of matches.
text = "spam, spam, spam"
needle = "spam"
last_index = text.rfind(needle)
if last_index == -1:
print("not found")
else:
print(last_index) # 12In this example, the final "spam" begins at index 12. The Python 3.14.8 built-in types documentation describes rfind() as returning the highest index where the substring is found, or -1 when it is absent.
Choose between rfind() and rindex()
Both methods search for the final occurrence; the difference is how they handle a missing substring.
#1 Best Overall
| Method | If a match exists | If no match exists | Use it when |
|---|---|---|---|
rfind(sub) |
Returns the highest matching index. | Returns -1. |
A missing match is an ordinary case you want to handle explicitly. |
rindex(sub) |
Returns the highest matching index. | Raises ValueError. |
A missing match should be treated as an error. |
For example, if you choose rindex() but want to turn the exception into a value, catch it:
try:
last_index = text.rindex(needle)
except ValueError:
last_index = NoneLimit the search to a range
rfind() and rindex() accept optional start and end arguments. These bounds follow slice-style interpretation, so you can search within a portion of the string:
text = "spam, spam, spam"
index = text.rfind("sp", 0, 10)
print(index) # 6The upper bound is handled like the end of a slice. See the official built-in types reference for the documented bounded-search behavior.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.When you need the text around the last separator
If you want the portions before and after the final separator rather than its numeric position, use rpartition(sep). It returns a three-item tuple: the text before the last separator, the separator itself, and the text after it.
What’s actually slowing this PC down?
Pick the symptom - the matching free tool is one click away.
path = "reports/2026/summary.txt"
before, separator, after = path.rpartition("/")
# before == "reports/2026"
# separator == "/"
# after == "summary.txt"If the separator is not found, rpartition() returns ('', '', original_string). The method is documented in Python’s built-in types reference.
Quick Recap
Common points to keep in mind
rfind()returns a string index, not a count of matches.str.count()answers a different question: it counts non-overlapping occurrences. For an empty substring,count()returns the string’s length plus one.- These methods operate on
strtext. If your input isbytes, use the corresponding bytes method or decode it before searching as text. Python documents the text and binary sequence methods in its built-in types reference.
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
