Guides
Anonymization
Replace detected PII with uniform placeholders.
Anonymization
Use anonymize() to replace every detected PII value with a fixed placeholder string.
Basic anonymization
from fastpii import FastPII, DEFAULT_PRIORITY
from fastpii.countries.cz import CzechPack
engine = FastPII(priority=DEFAULT_PRIORITY)
engine.register(CzechPack())
text = "Email: jan.novak@example.cz, RČ: 8001011238"
result = engine.anonymize(text)
print(result)Output:
Email: [REDACTED], RČ: [REDACTED]Custom replacement
result = engine.anonymize(text, replacement="<PII>")
print(result)Output:
Email: <PII>, RČ: <PII>Using TransformationEngine directly
For more control, use the TransformationEngine with AnonymizeStrategy:
from fastpii.core.transform import TransformationEngine, AnonymizeStrategy
result = engine.detect(text)
anonymized = TransformationEngine.apply(result, AnonymizeStrategy(replacement="[PRIVATE]"))
print(anonymized)Output:
Email: [PRIVATE], RČ: [PRIVATE]When to use anonymization
Anonymization is best when:
- You need a uniform placeholder regardless of PII type
- Preparing text for LLM prompts where type labels are unnecessary
- Writing logs where all PII should be treated equally