💡 R = decimal point — e.g. 4R7 = 4.7 Ω, 0R22 = 0.22 Ω, R10 = 0.1 Ω
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Resistance Value
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Exact Value
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in ohms
Tolerance
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typical
Typical Use
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Nearest E24 Standard Values
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Please enter a valid resistance value (≥ 0).
SMD codes for —
No exact standard code found. Consider the nearest E24/E96 value.
🔍 Most Searched SMD Codes — click to decode instantly
📋 Code System Reference
Code
System
Resistance
Calculation
Tolerance
Series
100
3-digit
10 Ω
10 × 10⁰
±5%
E24
220
3-digit
22 Ω ⚠️
22 × 10⁰ ← NOT 220Ω
±5%
E24
472
3-digit
4.7 kΩ
47 × 10²
±5%
E24
103
3-digit
10 kΩ
10 × 10³
±5%
E24
684
3-digit
680 kΩ
68 × 10⁴
±5%
E24
1000
4-digit
100 Ω
100 × 10⁰
±1%
E96
4702
4-digit
47 kΩ
470 × 10²
±1%
E96
1001
4-digit
1 kΩ
100 × 10¹
±1%
E96
4R70
R-notation
4.70 Ω
R = decimal point
±1%
—
0R22
R-notation
0.22 Ω
R = decimal point
±1%
—
01C
EIA-96
10 kΩ
100 × 100 (C)
±1%
E96
68B
EIA-96
4.99 kΩ
499 × 10 (B)
±1%
E96
96A
EIA-96
976 Ω
976 × 1 (A)
±1%
E96
Letter
Multiplier
Letter
Multiplier
Z
×0.001
A
×1
Y / R
×0.01
B / H
×10
X / S
×0.1
C
×100
—
—
D
×1,000
—
—
E
×10,000
—
—
F
×100,000
📦 SMD Package Sizes & Power Ratings
01005
0.4 × 0.2 mm
1/32 W · 31 mW
Wearables, hearing aids
0201
0.6 × 0.3 mm
1/20 W · 50 mW
Smartphones
0402
1.0 × 0.5 mm
1/16 W · 62 mW
Modern PCBs
0603
1.6 × 0.8 mm
1/10 W · 100 mW
General purpose
0805
2.0 × 1.25 mm
1/8 W · 125 mW
Consumer boards
1206
3.2 × 1.6 mm
1/4 W · 250 mW
Power circuits
⚡ Quick Engineering Tips
3-digit = ±5% (E24 series)
Used on standard-tolerance resistors. Last digit is a power-of-10 multiplier. 472 = 47 × 10² = 4.7 kΩ.
⚠️ 220 ≠ 220 Ω — most common mistake
The code 220 means 22 × 10⁰ = 22 Ω. The last digit is ALWAYS a multiplier, not part of the value. 221 = 220 Ω.
4-digit = ±1% (E96 series)
Higher precision. First 3 digits are significant, 4th is multiplier. 4702 = 470 × 10² = 47 kΩ. Smaller components often use EIA-96 instead.
EIA-96 — 3 characters, 1% precision
Two digits look up a base value from a 96-entry table, then a letter gives the multiplier. 01C → 100 Ω × 100 = 10 kΩ.
R-notation = decimal point
When resistance is below 10 Ω (3-digit) or 100 Ω (4-digit), 'R' replaces the decimal. 4R7 = 4.7 Ω, 0R22 = 0.22 Ω, R10 = 0.1 Ω.
000 = 0 Ω jumper / wire link
A chip marked 000 is a zero-ohm resistor used as a PCB wire bridge. It has essentially no resistance and is used for routing signals on single-layer boards.
Understanding SMD Resistor Codes
Surface-mount (SMD) resistors are too small for color bands. Instead, a compact code is printed on the top face. Three systems exist: 3-digit, 4-digit, and EIA-96 — each with different precision and decoding rules.
The first two digits are the significant value, and the third digit is a multiplier (power of 10). For example: 472 → 47 × 10² = 4,700 Ω = 4.7 kΩ. When the multiplier digit is 9, it means ×0.1. When the code contains 'R', it marks the decimal point (e.g. 4R7 = 4.7 Ω).
22 Ω — not 220 Ω. This is the most common mistake beginners make. The last digit (0) is a multiplier: 10⁰ = 1. So 220 = 22 × 1 = 22 Ω. If you needed 220 Ω, the code would be 221 (22 × 10¹ = 220 Ω).
EIA-96 is used on 1% precision resistors from the E96 value series, especially on very small packages (0402 and below) where 4 digits won't fit. A 2-digit number (01–96) identifies a base value from a lookup table, followed by a letter multiplier. Example: 01C → base 100 Ω × C (×100) = 10 kΩ. The 96 possible base values correspond exactly to the E96 resistor series.
The letter R acts as a decimal point. It is used when the resistance value is below 10 Ω (for 3-digit codes) or below 100 Ω (for 4-digit codes), where a multiplier digit isn't needed. Examples:
Use the Reverse Lookup tab above. Enter the resistance value and select the unit (Ω, kΩ, MΩ). The tool will show you all valid SMD codes — 3-digit (±5%), 4-digit (±1%), and EIA-96 (±1%) — for that value. Note that not all arbitrary resistance values have a corresponding standard code; the tool will show the nearest E24 or E96 value if an exact match isn't found.
3-digit codes offer 2 significant digits and are used on standard ±5% tolerance resistors from the E24 series. 4-digit codes offer 3 significant digits and are used on precision ±1% resistors from the E96 series. The extra digit allows much finer values — for example, 3-digit can give you 47 kΩ (472), but 4-digit can give you 47.5 kΩ (4752). For most hobbyist circuits, 3-digit codes are sufficient.
SMD resistor packages are named by their imperial dimensions in hundredths of an inch. The most common sizes are: 0402 (1.0 × 0.5 mm, 1/16 W), 0603 (1.6 × 0.8 mm, 1/10 W), 0805 (2.0 × 1.25 mm, 1/8 W), and 1206 (3.2 × 1.6 mm, 1/4 W). In general, the smaller the package, the lower the power rating. Always check the datasheet if power dissipation is critical.
A resistor marked 000 is a zero-ohm resistor (also called a jumper or wire link). It has essentially zero resistance and is used as a PCB bridge — to route a signal across a trace on single-layer boards, or to provide a configurable option link on a board. They're soldered and removed just like any other SMD resistor, which makes automated assembly much easier than soldering a wire.
When Should I Use Each Code System?
Use 3-digit when tolerance isn't critical — LED current limiting, pull-up networks, voltage dividers for non-sensitive signals. Use 4-digit or EIA-96 when you need precision — op-amp feedback networks, ADC reference dividers, precision current sensing, RF matching networks. Most hobbyist projects work perfectly with 5% (3-digit) resistors.