Vellum prepares a document for long-term archiving in the PDF/A-2B format, in either a conforming mode — rasterised pages, ISO 19005-2 conformance validated with veraPDF — or a faithful mode, which preserves the text without guaranteeing conformance. The conversion runs on your device, and no file is ever sent to a server.
Vellum — free PDF tools whose processing stays on your device.