Data Mask Studio vs Libelle DataMasking

Data Mask Studio is a free Windows desktop application for masking sensitive data in CSV files and local HTML content. Users can choose columns to preserve, mask, or exclude; normalize, rename, or compose columns; and reuse profiles for batch work. CSV files can be processed individually or in batches, with selective restoration available later. Its deterministic tokens can keep repeated values consistent across records and files. The app can also restore known codes in local HTML files and dashboards while preserving their markup. Original values and mappings remain in an encrypted local vault, which is needed for restoration. The maker says tokens use HMAC-SHA256, vault data uses AES-256-GCM, and Windows DPAPI protects local keys. Processing stays local, without telemetry or automatic synchronization. Additional tools include password-protected portable backups, vault integrity audits, diagnostics, temporary-file cleanup, and controlled compaction. Large files use bounded-memory streaming. Releases offer a per-user Windows installer and portable ZIP. The app is licensed under GPL-3.0-only. It does not guarantee irreversible anonymization, and its executables are not digitally signed yet, so Windows may show a SmartScreen warning.

Libelle DataMasking has no write-up on Specifiction yet; its figures are above.