555 Timer LED Blinker Simulator
Build and run a classic 555 timer blinker instantly in your browser — no installation, no account required. Watch VoltForge wire up the circuit step by step, then see the LED flash as the timer runs live.
How a 555 blinker works
In astable mode, the 555 timer charges and discharges a capacitor through two resistors, switching its output on and off over and over. That output drives an LED, so it blinks. The resistor and capacitor values set how fast it flashes and how long it stays lit.
Try it now
Open the simulator below to watch the 555 blinker build itself, then change the parts and see what happens.