Basalt for Mac

Basalt is a native macOS PDF toolkit that brings eighteen document tools into a single window and processes every file locally on your Mac.

Most PDF tools redact by drawing a black rectangle over text that remains in the file, which is why redaction failures keep reaching the news. Basalt removes the content instead. Text is excised glyph by glyph, image pixels are destroyed and re-encoded, and annotations and paths are dropped. It then re-opens the file it has just written using an independent parser and searches for the material again. If anything is found, no file is written at all.

Features

• Redaction that destroys content rather than covering it, verified before the file is saved.
• Ed25519 certificate of redaction on every export, re-verifiable by a third party without a copy of Basalt.
• Byte-reproducible output: the same input and the same marks always produce an identical file.
• Inspector reports eleven classes of hidden data in any PDF, including documents Basalt did not create.
• Whole-document sanitisation of metadata, XMP, attachments, embedded JavaScript and hidden optional-content layers.
• Merge, split, and page organisation with rendered thumbnails, drag-to-reorder, rotation and deletion.
• Compression with Email, Balanced, Print and Custom presets; output size is measured before writing and never exceeds the original.
• OCR through Apple's Vision framework, adding an invisible searchable text layer to scans.
• Bates numbering with a registry, collision detection and a CSV manifest, across single files or a full batch.
• Privilege log generated directly from redaction marks, exported to CSV or XLSX.
• Form filling with regenerated appearances and flattening on export.
• Signing by drawing, typing, or importing a photograph with the background lifted away.
• Watermarks, headers, footers and page numbering with tokens, tiling, opacity and page scope.
• Password protection using AES-256, and password removal.
• Images to PDF, and pages exported to PNG or JPEG at a chosen resolution.
• Text-level document comparison with a blackline export
• Named procedures that chain OCR, redaction, Bates numbering, flattening, watermarking and compression into a repeatable run.
• Large documents open without being loaded into memory: opens in well under a second.
• Finder Services integration, Quick Look badging for documents carrying unapplied marks, full keyboard operation and VoiceOver labelling.

Privacy is enforced rather than promised. The engine that separate XPC service holding no network entitlement, whichmacOS enforces at the code-signature level, so documents cannot leave the machine. There is no account, no telemetry and no cloud component.