Lotus 1-2-3 ran the ’80s and ’90s; Quattro Pro fought it for a decade. The numbers in those files are still good — out they come, into Excel, CSV or PDF.
Lotus 1-2-3 across its whole life: .wk1 (v2, the DOS standard), .wk3 and .wk4 (Windows era), and .123 (Millennium/97). Quattro Pro: .wb1 through .wb3 and the later .qpw. The readers are libwps and LibreOffice’s Lotus filters — the most complete free implementations these formats have.
Values always survive — that’s usually what matters after thirty years. Common formulas (arithmetic, SUM and friends) translate; exotic @functions and macros don’t, and cells fall back to their last computed value. Choose CSV if you only want the raw numbers (first sheet of multi-sheet files), XLSX to keep sheets and formatting, PDF for a snapshot.
It’s written to a private temporary folder for the few seconds the conversion engine needs, then deleted — nothing is retained, logged or shared. No account, no email, no “files kept for 24 hours” fine print. These are often someone’s letters, family records or old business files; we treat them accordingly.