Calculator for resistor in base of transistor by Marjan Shtrkoski.
Ic – Collector current
Hfe – Transistor gain “beta”
Vb – Base Supply voltage
Vbe – Voltage drop
Rb – Base resistor value
Calculate the current you need to pass through the transistor when its on, that is your collector current.
The current gain, beta, Hfe, is a value you can find in the datasheet for the specific transistor.
Supply voltage is the voltage that you use to drive the base of the transistor with.
Download Program : Transistor base resistor calculator
Thank you Marjan!!