Understanding Electronics www.
kitronik.
co.
uk Resistor Values
www.
kitronik.
co.
uk Page 1 of 3
Kitronik Ltd – How to Calculate and Understand Resistor Values
Resistors
A resistor is a device that opposes the flow of electrical current.
The bigger the...
More
Understanding Electronics www.
kitronik.
co.
uk Resistor Values
www.
kitronik.
co.
uk Page 1 of 3
Kitronik Ltd – How to Calculate and Understand Resistor Values
Resistors
A resistor is a device that opposes the flow of electrical current.
The bigger the value of a resistor the more
it opposes the current flow.
The value of a resistor is given in Ω (ohms) and is often referred to as its
‘resistance’.
Identifying Resistor Values
Band Colour 1st Band 2nd Band Multiplier x Tolerance
Silver 100 10%
Gold 10 5%
Black 0 0 1
Brown 1 1 10 1%
Red 2 2 100 2%
Orange 3 3 1000
Yellow 4 4 10,000
Green 5 5 100,000
Blue 6 6 1,000,000
Violet 7 7
Grey 8 8
White 9 9
Example: Band 1 = Red, Band 2 = Violet, Band 3 = Orange, Band 4 = Gold
The value of this resistor would be:
2 (Red) 7 (Violet) x 1,000 (Orange) = 27 x 1,000
= 27,000 with a 5% tolerance (gold)
= 27kΩ
Too many zeros?
kilo ohms and mega
ohms can be used:
1,000Ω = 1k
1,000K = 1M
Less
