555 Timer Calculator

Calcforall May 29, 2025

555 Timer Calculator – Astable Mode Frequency & Duty Cycle

555 Timer Calculator (Astable Mode)

Use this free 555 timer calculator to determine the output frequency, time high, time low, and duty cycle of your astable circuit based on your selected resistor (R1, R2) and capacitor (C) values.

555 Timer Astable Mode Circuit Diagram

Resistor R1 (kΩ): Resistor R2 (kΩ): Capacitor C (μF):

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