Timers are the common feature of any microcontroller. A timer is also known as register. Timers commonly have a resolution of 8 (or) 16 bits. So a 8 bit timer is 8 bits wide so capable of holding value within 0-255. An AVR (Advanced Virtual Risc) microcontroller has effective and multifunctional clocks. In this calculator, calculate the AVR timer based on the known values of total timer ticks, overflow count, real time and new frequency.