pdfxup

N-up PDF pages. N-upping means putting multiple pages onto one page by scaling and rotating them into a grid. More information: https://ctan.org/pkg/pdfxup.

pdfxup -o path/to/output.pdf path/to/input.pdf

pdfxup -x 3 -y 2 -o path/to/output.pdf path/to/input.pdf

pdfxup -b -o path/to/output.pdf path/to/input.pdf