SMD Resistor Code Calculator | 3-digit, 4-digit & EIA-96

Decoded value

3-digit

The first two digits are significant figures and the third digit is the power-of-ten multiplier.

4-digit

The first three digits are significant figures and the fourth digit is the multiplier.

EIA-96

Two digits select an E96 base value and the letter sets the multiplier used in precision SMD parts.

How to use the SMD resistor code calculator

Read the marking printed on the resistor package, type it into the input, and leave the selector on auto-detect unless you already know the family. The calculator normalizes the code, identifies the format, and returns the nominal resistance value immediately.

What SMD resistor markings mean

Surface-mount resistors rarely have room for full printed values, so manufacturers encode the resistance into short markings. Many general-purpose parts use 3-digit or 4-digit numeric codes, while tighter-tolerance resistors often use the EIA-96 system. Knowing how to decode them saves time when reading boards, checking BOM substitutions, or confirming that the assembled value matches the design intent.

If you are also dealing with through-hole parts, the resistor color code calculator is the natural companion. And once you know the value, the resistor network calculator helps you combine it with the rest of the circuit.

Supported code families

  • 3-digit codes such as 472 mean 47 × 10² = 4.7 kΩ.
  • 4-digit codes such as 1001 mean 100 × 10¹ = 1 kΩ.
  • EIA-96 codes such as 01C use a lookup table for the first two digits and a letter multiplier, giving 10 kΩ in this example.

Worked examples

472 decodes to 4.7 kΩ.

1001 decodes to 1 kΩ.

01C uses the EIA-96 value 100 with multiplier C = 100, so it becomes 10 kΩ.

Frequently Asked Questions

  • What does a 3-digit SMD resistor code mean?
    The first two digits are the significant value and the third digit tells you how many zeros to add.
  • When are 4-digit codes used?
    They are common on higher-precision chip resistors because they allow three significant digits before the multiplier.
  • What is EIA-96?
    EIA-96 is a coding system for precision resistors that uses 96 preferred values plus a letter multiplier.
  • Can this calculator decode every SMD marking style?
    This version focuses on the most common printed families: 3-digit, 4-digit, and EIA-96.

EIA-96 code table and multipliers

The EIA-96 system works in two steps. First, match the two-digit code to the preferred E96 base value in the table below. Then apply the letter multiplier. For example, 01C means base value 100 with multiplier C = 100, so the result is 10 kΩ.

EIA-96 base codes

These two-digit codes map to the 96 preferred resistor values used on precision SMD parts.

Code Base value Ω reference
01 100 Ω
02 102 Ω
03 105 Ω
04 107 Ω
05 110 Ω
06 113 Ω
07 115 Ω
08 118 Ω
09 121 Ω
10 124 Ω
11 127 Ω
12 130 Ω
13 133 Ω
14 137 Ω
15 140 Ω
16 143 Ω
17 147 Ω
18 150 Ω
19 154 Ω
20 158 Ω
21 162 Ω
22 165 Ω
23 169 Ω
24 174 Ω
25 178 Ω
26 182 Ω
27 187 Ω
28 191 Ω
29 196 Ω
30 200 Ω
31 205 Ω
32 210 Ω
33 215 Ω
34 221 Ω
35 226 Ω
36 232 Ω
37 237 Ω
38 243 Ω
39 249 Ω
40 255 Ω
41 261 Ω
42 267 Ω
43 274 Ω
44 280 Ω
45 287 Ω
46 294 Ω
47 301 Ω
48 309 Ω
49 316 Ω
50 324 Ω
51 332 Ω
52 340 Ω
53 348 Ω
54 357 Ω
55 365 Ω
56 374 Ω
57 383 Ω
58 392 Ω
59 402 Ω
60 412 Ω
61 422 Ω
62 432 Ω
63 442 Ω
64 453 Ω
65 464 Ω
66 475 Ω
67 487 Ω
68 499 Ω
69 511 Ω
70 523 Ω
71 536 Ω
72 549 Ω
73 562 Ω
74 576 Ω
75 590 Ω
76 604 Ω
77 619 Ω
78 634 Ω
79 649 Ω
80 665 Ω
81 681 Ω
82 698 Ω
83 715 Ω
84 732 Ω
85 750 Ω
86 768 Ω
87 787 Ω
88 806 Ω
89 825 Ω
90 845 Ω
91 866 Ω
92 887 Ω
93 909 Ω
94 931 Ω
95 953 Ω
96 976 Ω

EIA-96 letter multipliers

After finding the base value, apply the letter multiplier to get the final resistance.

Letter Multiplier Example
Z 0.001 100 × 0.001 = 0.1 Ω
Y 0.01 100 × 0.01 = 1 Ω
R 0.01 100 × 0.01 = 1 Ω
X 0.1 100 × 0.1 = 10 Ω
S 0.1 100 × 0.1 = 10 Ω
A 1 100 × 1 = 100 Ω
B 10 100 × 10 = 1 kΩ
H 10 100 × 10 = 1 kΩ
C 100 100 × 100 = 10 kΩ
D 1000 100 × 1000 = 100 kΩ
E 10000 100 × 10000 = 1 MΩ
F 100000 100 × 100000 = 10 MΩ

About the author: This tool was built by Miguel P.. I'm a space-sector electronic designer who got tired of "half-working calculators." I build these to be the fast, helpful tools I need at my own workbench.

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