PII Arena
HF detector

mmbert32k PII detection benchmark

Measured on 41 of 41 retained datasets under the same frozen scoring and masking protocol.

50.17%fully hidden annotations
78.53%detected / overlapped
10.33%extra masking
4,313CPU characters / second

Strengths

Highest complete-masking rates by normalized data type.

Dates & times82.81%4,556 / 5,502
People's names74.29%48,838 / 65,736
Documents & identifiers61.41%9,232 / 15,034

Watch list

Lowest observed complete-masking rates; inspect before deployment.

Organizations15.88%3,061 / 19,274
Other sensitive attributes20.30%651 / 3,207
Customer & employee IDs27.75%2,218 / 7,994

Language coverage

The overall leader can differ from the best choice for one language slice.

LanguageDatasetsFully hidden ↑Detected ↑Extra masking ↓
English1758.34%79.33%11.78%
Russian1942.57%75.98%7.27%
Multilingual563.85%84.48%2.97%

Configuration, source and version

Family
HF
Revision
d22c818cf9f2a8bfbbed8508cb417dc16a1ba3ea
Eligible datasets
41 / 41
Character F1
0.613
Untouched diagnostic
21.47% · 48,833 / 227,466
Benchmark version
1.0.3 · 2026-09-09
CPU seconds / 10k chars
2.319
GPU seconds / 10k chars
0.183

Results by dataset

Complete masking is primary; detection shows whether any character overlapped.

DatasetGold annotationsFully hidden ↑Detected ↑Extra masking ↓
rubai-ru3,4585.67%98.38%
tab-echr3,83014.54%47.39%
synth-secrets-en58120.83%78.31%33.00%
synth-secrets-ru58122.03%76.59%33.94%
alexen21,26122.60%98.33%8.11%
leak-museum10122.77%42.57%2.71%
synth-env-configs39225.26%86.99%23.32%
multiconer-ru1,20827.98%53.56%6.96%
synth-wiki-tables13,09428.52%86.99%
nerel24,36934.06%48.84%
leaky-repo9534.74%66.32%3.15%
corrupt-secrets-issues28835.07%83.33%8.84%
synth-ru-tickets32,09939.99%80.56%
redact-ru9,23040.94%78.21%9.26%
factrueval7,96642.19%45.78%
alrosait1,86243.98%98.23%3.27%
secrets-issues28844.44%81.60%9.77%
dialogpii-en3,08746.65%64.53%4.85%
synth-jira-comments2,70547.28%88.54%
jayguard1,19548.79%79.41%3.12%
dialogpii-multi10,34549.71%68.42%
scanpatch8,70850.42%83.77%1.34%
corrupt-redmadrobot5,53150.99%79.30%2.83%
ameau012,24252.05%77.79%4.59%
gretel-multi4,48456.31%77.30%2.93%
secrets-rules74656.43%93.83%48.11%
redmadrobot5,51659.30%81.24%2.54%
privy1,89960.40%77.62%6.08%
creddata77660.70%89.43%10.19%
corrupt-hivetrace1,66761.79%95.02%4.08%
nemotron-pii9,39162.01%86.40%3.10%
tonicai2,41762.10%73.85%0.40%
redact-multi22,86462.39%89.25%
nym-ru9,49763.43%91.51%
hivetrace1,66774.75%96.70%0.37%
kiji-multi7,56575.61%87.10%
russian-pii-66k4,80575.96%97.36%
kiji-en7,62377.45%87.16%
nym-en3,58477.57%91.41%4.02%
nym-multi8,16979.09%93.01%5.81%
arthur-passwords28082.14%82.14%16.37%