There are currently 11 resistors integrated into circuito.io. Resistors are peripheral components, that are added to the circuit automatically by circuito.io and their purpose is to control the amount of electricity that flows through the circuit.
A resistor’s value is marked by colored stripes printed on the resistor itself. Here is a list of resistors and their values:
47 Ohm Resistor - 
100 Ohm Resistor- 
220 Ohm Resistor- 
330 Ohm Resistor- 
470 Ohm Resistor- 
1K Ohm Resistor- 
3.3K Ohm Resistor- 
4.7K Ohm Resistor- 
10K Ohm Resistor- 
22K Ohm Resistor- 
1M Ohm Resistor- 