Resistors
are one of the four fundamental types of passive electronic components; the other
three are the inductor, the
capacitor, and the
memristor.
The basic unit of resistance is the ohm (Ω).
Standard base resistor values are given in the following tables for the most
commonly used tolerances (1%, 2%, 5%, 10%), along
with typically available resistance ranges. To determine values other than the base,
multiply the base value by 1, 10, 100, 1k, or 10k.
Standard resistor values are calculated
using the simple formula given below. Round the results to the proper number of
significant figures (three for 1% and 2%, two for 5% and
10%). As the chart at the right shows
(created in Excel), plotting the values on
a logarithmic scale results in a straight line due to the exponential in the equation.
 
Example: Calculations indicate the need for a 355 kΩ resistor
and a tolerance of 1%. Look in the 1% table and select the 35.7 value
(the nearest available standard value). Multiply by
10,000 to convert to 357 kΩ.
10.0 |
10.2 |
10.5 |
10.7 |
11.0 |
11.3 |
11.5 |
11.8 |
12.1 |
12.4 |
12.7 |
13.0 |
13.3 |
13.7 |
14.0 |
14.3 |
14.7 |
15.0 |
15.4 |
15.8 |
16.2 |
16.5 |
16.9 |
17.4 |
17.8 |
18.2 |
18.7 |
19.1 |
19.6 |
20.0 |
20.5 |
21.0 |
21.5 |
22.1 |
22.6 |
23.2 |
23.7 |
24.3 |
24.9 |
25.5 |
26.1 |
26.7 |
27.4 |
28.0 |
28.7 |
29.4 |
30.1 |
30.9 |
31.6 |
32.4 |
33.2 |
34.0 |
34.8 |
35.7 |
36.5 |
37.4 |
38.3 |
39.2 |
40.2 |
41.2 |
42.2 |
43.2 |
44.2 |
45.3 |
46.4 |
47.5 |
48.7 |
49.9 |
51.1 |
52.3 |
53.6 |
54.9 |
56.2 |
57.6 |
59.0 |
60.4 |
61.9 |
63.4 |
64.9 |
66.5 |
68.1 |
69.8 |
71.5 |
73.2 |
75.0 |
76.8 |
78.7 |
80.6 |
82.5 |
84.5 |
86.6 |
88.7 |
90.9 |
93.1 |
95.3 |
97.6 |
10.0 |
10.5 |
11.0 |
11.5 |
12.1 |
12.7 |
13.3 |
14.0 |
14.7 |
15.4 |
16.2 |
16.9 |
17.8 |
18.7 |
19.6 |
20.5 |
21.5 |
22.6 |
23.7 |
24.9 |
26.1 |
27.4 |
28.7 |
30.1 |
31.6 |
33.2 |
34.8 |
36.5 |
38.3 |
40.2 |
42.2 |
44.2 |
46.4 |
48.7 |
51.1 |
53.6 |
56.2 |
59.0 |
61.9 |
64.9 |
68.1 |
71.5 |
75.0 |
78.7 |
82.5 |
86.6 |
90.9 |
95.3 |
10 |
11 |
12 |
13 |
15 |
16 |
18 |
20 |
22 |
24 |
27 |
30 |
33 |
36 |
39 |
43 |
47 |
51 |
56 |
62 |
68 |
75 |
82 |
91 |
10 |
12 |
15 |
18 |
22 |
27 |
33 |
39 |
47 |
56 |
68 |
82 |
* A nimrod keeps contacting me to say there is no such thing as a real memristor.
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