555 Timer Calculator

The 555 timer is a commonly used integrated circuit that can be configured to produce a square waveform output. In Astable configuration the output will be a free running squarewave output. In Monostable mode the output will be a single high pulse generated for a single input event. This calculator will determine the pulse width of the output based on the resistance and capacitance values entered.

Monostable

Please enter your values below.

Formulas

T = 1.1RC

Diagram View

Monostable

Astable

Please enter your values below.

Formulas

Thigh = 0.693(R1 + R2)CTlow = 0.693R2Cf = 1.44/((R1 + 2R2)C)

Diagram View

Astable