ascii()

ascii(object)

Returns: str · Updated March 13, 2026 · Built-in Functions

built-in string representation debugging

The ascii() function returns a string containing a printable representation of an object. It escapes non-ASCII characters using \x, \u, or \U escape sequences, making it useful for debugging and logging.

Syntax

ascii(object)

Parameters

Parameter	Type	Description
`object`	any	Any Python object (string, list, dict, custom class, etc.)

Examples

Basic usage with strings

text = "hello world"
print(ascii(text))
# 'hello world'

# Non-ASCII characters get escaped
text = "café"
print(ascii(text))
# 'caf\\xe9'

Working with unicode strings

# Emoji gets escaped
message = "Hello 👋"
print(ascii(message))
# 'Hello \\U0001f44b'

# Chinese characters
text = "你好"
print(ascii(text))
# '\\u4f60\\u597d'

With lists and dictionaries

data = ["apple", "café", 42]
print(ascii(data))
# ['apple', 'caf\\xe9', 42]

mixed = {"name": "José", "emoji": "🎉"}
print(ascii(mixed))
# {'name': 'Jos\\xe9', 'emoji': '\\U0001f389'}

With custom objects

class Person:
    def __init__(self, name):
        self.name = name

person = Person("Renée")
print(ascii(person))
# <__main__.Person object at 0x...>

Common Patterns

Debug logging with ascii()

import logging

logging.basicConfig(level=logging.DEBUG)

def process_user_input(user_data):
    # Safely log user input that might contain special characters
    logging.debug(f"Processing: {ascii(user_data)}")
    # Output: Processing: {'name': 'J\\xf6rg', 'city': 'M\\xfcnchen'}

process_user_input({"name": "Jörg", "city": "München"})

Sanitizing output for logs

def log_response(response_data):
    # ascii() ensures log files stay ASCII-safe
    with open("app.log", "a") as f:
        f.write(ascii(response_data) + "\n")

log_response("User said: héllo wörld")
# File contains: User said: h\\xe9llo w\\xf6rld

Comparing representations

# Compare objects ignoring Unicode normalization
a = "café"
b = "café"  # Different unicode codepoint representation
print(a == b)        # Might be False depending on input
print(ascii(a) == ascii(b))  # Useful comparison

n## How It Works

The function is similar to but with an important difference: it forces all non-ASCII characters to be escaped. This makes it useful when you need to guarantee that output contains only ASCII characters, such as writing to log files or debugging output that must be ASCII-safe.

When encounters a Unicode character, it uses the following escape sequences:

for characters in the range 0x00-0xFF
for characters in the range 0x0100-0xFFFF
for characters beyond 0xFFFF

This escaping ensures output can be decoded by any ASCII-compatible encoding.

How It Works

The function is similar to but with an important difference: it forces all non-ASCII characters to be escaped. This makes it particularly useful when you need to guarantee that output contains only ASCII characters, such as when writing to log files or debugging output that must be ASCII-safe.