Most document redactors either upload your file to a third-party API or paint rectangles over text that's still selectable underneath. Maskify keeps the original PDF/DOCX in your browser; only the extracted text is sent for detection. PDF export is rasterised, so the original bytes are physically removed — DOCX is edited in-place, preserving styles and images. Hybrid detection: in-house AI plus validated regex (IBAN, card, DNI) and your own saved patterns. Reversal map only you hold.