No, there is not standard "records per inch" calculation due to too many variables. Just take some average records and measure how many make up an inch.
Is there a standard for number of LP's per inch?
I want to get an idea of how many LPs I own. Is there an agreed-upon standard for how many discs are in a running inch, or foot? There is a lot of variation so it would be helpful to know if this is a known quantity.