Python 3.7+Strings (str)function

str.isascii

character checks

True if the string is empty or all characters are ASCII.

Syntax

s.isascii()

Added in Python 3.7, and unlike the other is-methods it returns True for the empty string. ASCII here means code points below 128, not printable: newline, tab and the null byte all pass. Handy as a cheap pre-check before encode('ascii'), or to catch a Cyrillic look-alike letter smuggled into an identifier.

Examples

print('abc'.isascii())     # → True
print('café'.isascii())    # → False
print(''.isascii())        # → True

See also

Open in the full glossarydocs.python.orgReport an inaccuracy