Email Local Part (Before @) in PY
Validate just the local part of an email address (the bit before the @).
Try it in the PY tester →Pattern
regexPY
^[a-zA-Z0-9._%+\-]{1,64}$Python (re) code
pyPython
import re
pattern = re.compile(r"^[a-zA-Z0-9._%+\-]{1,64}$")
input_text = "john.doe"
for m in pattern.finditer(input_text):
print(m.group(0))Stdlib `re` module — no third-party dependency. Works on Python 3.6+.
How the pattern works
^ and $ anchor to the full string. [a-zA-Z0-9._%+\-] is the conservative local-part character set (dots, underscores, percent, plus, hyphen for sub-addressing). {1,64} enforces the RFC max length for the local part.
Examples
Input
john.doeMatches
john.doe
Input
user+tagMatches
user+tag
Input
has spaceNo match
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