I am currently using 40g coffee to 500g water which is 12.5g coffee to 1g water but I have seen things like this https://www.olympiacoffee.com/blogs/blog/how-to-brew-like-olympia-coffee#:~:text=For those of you who,use 16.7 grams of water. which suggest using a little more. Does it even matter to adjust the ratio precisely if I don’t have a precision grinder and am using a Krups blade grinder? I am trying to get things as precise as possible.
I personally do a 20g:300ml for hot coffee or 20g: ~320ml for iced coffee (only approximate because of the ice cubes)
So that ends up being a 15ml per 1g
Also i think you mixed up coffee and water in your post, isn’t it 12.5g water to 1g coffee.
Consistency allows for reproducible results but there’s diminishing returns at a certain point. My grinder is the type that has a big hopper and runs for χ amount of seconds and I don’t notice a difference even though it can be up to 1g up or down.