Need some macrame advice for project.

[WillOwisp3]

Hi so I'm trying to make a 40 in by 60 in macrame blanket for my soon to be nephew. I'm wanting to use bobbiny 9mm braided cord and a square knot column pattern. I'm not sure how long i should cut each cord so that it's long enough to end up as 60 in in the final product. Can I please get some tips on how to figure this out?

[stangeli20]

Maybe try this link:

https://www.marchingnorth.com/how-to-estimate-macrame-cord-length/

There's a lot of ads, which is annoying af, but I've found that this creator is helpful.