What the calculation means
We compare 12 calendar-month payments with 13 four-week payments. Thirteen four-week periods cover 364 days. This normalizes the recurring price; it is not the exact cash charged between two dates. A charge on day 364 can begin the next period within a 365-day window.
What it leaves out
The calculator assumes a constant price and continuous billing. Introductory rates, prepaid terms, medication quantities, refill schedules and cancellations can change the bill. The monthly equivalent spreads 13 payments across 12 months for comparison; it does not change the payment schedule.
Use the evidence alongside the tool
Read the related guide, prepare provider questions, and compare researched services.