555 Timer Calculator

Calculate frequency and timing for 555 timer circuits. Supports astable (oscillator) and monostable (one-shot) modes.

555 Timer Calculator

Calculate frequency and timing for 555 timer circuits

Mode

R1 (Ω)

R2 (Ω)

Capacitor (F)

Common Capacitor Values

Formula

f = 1.44 / ((R1 + 2×R2) × C)