What is meant by a perquisite rate? How do I calculate that?

What is meant by a perquisite rate? How do I calculate that?

When your employer provides you or any member of your household, an interest free loan or a loan at a concessional rate – it is chargeable to tax as a perquisite.

Zoho Payroll automatically calculates the perquisite charges for a loan once you input the perquisite rate. Ideally, it should match the SBI interest rate.