For the original DOS-based versions (Lotus 1-2-3 Release 2.4 or 3.1+), DOSBox is the most accessible solution. DOSBox emulates an entire 286/386 environment, including the necessary VGA graphics and sound. Configuration requires mounting a directory as C: and adjusting cycles for speed accuracy. DOSBox-X, a more feature-rich fork, includes built-in support for loading .WK1 files and emulating the Lotus/Intel/Microsoft (LIM) expanded memory standard, which is critical for large spreadsheets. Performance is generally excellent, though printing requires redirection to text or PDF.
Simply enabling “Windows 95 compatibility mode” on a 64-bit Windows 10 system does not resolve the fundamental 16-bit execution barrier. Compatibility mode only modifies how the Windows API handles paths, DPI scaling, and user privileges; it does not emulate a 16-bit processor or the VxD kernel layer.
The inability to run original software on modern OSes risks losing the ability to verify computational results from historical spreadsheets. Financial audits, engineering calculations, and scientific data from the 1980s–1990s may depend on specific quirks of Lotus’s floating-point implementation (e.g., different rounding behavior from Excel). Running original binary code in a controlled emulator is the only method that guarantees bit-exact reproducibility.