How do I append one string to another in Python?

David Y.

—August 15, 2023

The ProblemThe Problem

Using Python, how should I append one string to another string and create one large string?

The SolutionThe Solution

There are a few different ways to do this. The simplest is to take advantage of Python’s operator overloading and add strings together, as below:

firstname = "Jane"
lastname = "Doe"

fullname = firstname + lastname # will be "JaneDoe"

We can also use the += operator to replace the value of our first variable with the combined string.

name = "Jane"
lastname = "Doe"

name += lastname # will be "JaneDoe"

In many cases, we will probably want our two strings to be separated by a space, comma, or other separator. We can achieve this in a couple of different ways, shown below:

firstname = "Jane"
lastname = "Doe"

# Adding three strings together:
fullname = firstname + " " + lastname

# Using str.join():
fullname = " ".join([firstname, lastname])

Both of these approaches will produce the string “Jane Doe”. The second one uses str.join, a string method that joins the strings in a provided list, separated by the string it’s called on. This approach is useful for combining large numbers of strings.

Yet another approach would be to use Python’s f-strings. This is useful for building more complex templates that we can slot existing strings into:

firstname = "Jane"
lastname = "Doe"

full_address = f"Ms. {firstname} {lastname}, M.A." # will be "Ms. Jane Doe, M.A."