Capacitor Value Calculator
Convert capacitor codes to values and find codes for specific values
Capacitor Value Calculator
Convert capacitor marking codes to values and find codes for specific values
Enter 2-3 digits optionally followed by tolerance letter (F, G, J, K, M)
Common Values
About Capacitor Codes
Ceramic capacitors use standardized EIA (Electronic Industries Alliance) marking codes following the IEC 60062 standard to indicate capacitance values and tolerances on small component bodies.
Code Structure:
- 3-digit codes: Two significant digits + multiplier (e.g., 104 = 10 × 10⁴ pF)
- 2-digit codes: Direct capacitance value in picofarads (e.g., 47 = 47 pF)
- Tolerance letters: Optional suffix indicating precision (J=±5%, K=±10%)
- Units: All calculations based on picofarads (10⁻¹² F)
Applications: Widely used in multilayer ceramic capacitors (MLCC), disc ceramics, and surface-mount components for filtering, coupling, and timing circuits.
Tolerance Codes Reference
Standard tolerance markings for ceramic capacitors:
Note: If no tolerance letter is specified, ±20% (M) is assumed for most ceramic capacitors.
Common Capacitor Values & Applications
Power Supply Filtering:
• 104 (100nF): Decoupling capacitor for digital ICs
• 105 (1µF): Power supply noise filtering
Signal Coupling:
• 223 (22nF): Audio coupling applications
• 473 (47nF): General AC coupling circuits
High-Frequency Circuits:
• 471 (470pF): RF bypass and tuning circuits
• 101 (100pF): Oscillator frequency determination
Calculation Examples & Tips
3-Digit Calculation:
• 104 = 10 × 10⁴ = 100,000pF = 100nF = 0.1µF
• 223K = 22 × 10³ = 22,000pF = 22nF ±10%
2-Digit Direct Values:
• 47 = 47pF (direct reading)
• 68 = 68pF (direct reading)
Pro Tips:
• Multiplier 0-6: 10⁰ to 10⁶ (1 to 1,000,000)
• Use reverse lookup to find nearest standard values
• Tolerance affects actual capacitance in circuit
2-3 digits + optional tolerance letter
Common Values
Quick Reference Guide
Code Examples & Calculations:
104 = 10 × 10⁴ = 100,000pF = 100nF = 0.1µF
223K = 22 × 10³ = 22,000pF = 22nF ±10%
471 = 47 × 10¹ = 470pF
47 = 47pF (direct value)
105J = 10 × 10⁵ = 1,000,000pF = 1µF ±5%
Unit Conversion:
1µF = 1,000,000pF = 1,000nF
1nF = 1,000pF = 0.001µF
1pF = 10⁻¹² Farads
Common Tolerance Codes:
Standard Values:
E12 Series: 10, 12, 15, 18, 22, 27, 33, 39, 47, 56, 68, 82
Each value × 10ⁿ (multipliers: 1, 10, 100, 1000, etc.)
Complete Guide to Capacitor Value Calculations
Understanding Ceramic Capacitor Codes
Ceramic capacitors are fundamental components in electronic circuits, used for filtering, coupling, decoupling, and timing applications. Due to their small physical size, manufacturers use standardized coding systems to mark capacitance values and tolerances directly on the component body.
The most common marking system follows the EIA (Electronic Industries Alliance) standard, also known as IEC 60062, which uses numeric codes to represent capacitance values in picofarads (pF).
Key Benefits of This Calculator:
- Instant conversion between codes and values
- Support for both 2-digit and 3-digit marking systems
- Tolerance calculation with standard letter codes
- Reverse lookup to find standard component values
- Multiple unit display (pF, nF, µF)
How Capacitor Codes Work
Three-Digit System
The three-digit system is the most widely used format. The first two digits represent the significant figures, while the third digit indicates the multiplier (power of 10).
↑ ↑ ↑
Significant digits | Multiplier
Result: 10 × 10⁴ = 100,000 pF = 100 nF = 0.1 µF
Two-Digit System
For smaller values (typically under 100 pF), manufacturers often use direct two-digit marking where the number represents the exact capacitance value in picofarads.
Direct value = 47 pF
Practical Applications & Circuit Design
Power Supply Decoupling
100 nF (0.1 µF)
Most common decoupling capacitor for digital ICs. Placed close to power pins to filter high-frequency noise and provide instantaneous current during switching.
Audio Coupling
22 nF (0.022 µF)
Common in audio circuits for AC coupling between amplifier stages. Blocks DC while allowing audio frequency signals to pass through.
RF Circuits
470 pF
Used in radio frequency applications for tuning circuits, oscillator feedback networks, and high-frequency bypass applications.
Tolerance and Precision in Capacitor Selection
Understanding Tolerance Codes
Tolerance indicates how much the actual capacitance can vary from the marked value. This is crucial for precision circuits where exact capacitance values are required.
Selecting the Right Tolerance
High Precision (±1% to ±2%)
Required for timing circuits, oscillators, and filter networks where exact values are critical.
Standard Precision (±5%)
Suitable for most general-purpose applications including decoupling and coupling circuits.
General Purpose (±10% to ±20%)
Acceptable for non-critical applications where slight variations won't affect circuit performance.
Frequently Asked Questions
What's the difference between ceramic and electrolytic capacitor codes?
This calculator specifically handles ceramic capacitor codes using the EIA standard. Electrolytic capacitors typically use direct value marking (e.g., "100µF 25V") rather than numeric codes, as they're large enough to accommodate full text marking.
Why do some capacitors only have 2 digits while others have 3?
Two-digit codes are used for smaller values (typically under 100pF) where the direct value fits easily. Three-digit codes allow representation of a much wider range of values using the multiplier system, making them more versatile for marking larger capacitances.
How accurate is the reverse lookup feature?
The reverse lookup uses standard E12 and E24 series values that manufacturers actually produce. It finds the closest available standard values to your target, ensuring you can actually purchase the suggested components from electronic suppliers.
What if my capacitor code doesn't work in the calculator?
Some older or specialized capacitors may use non-standard marking systems. This calculator handles the most common EIA/IEC 60062 standard used by major manufacturers. If your code doesn't work, check for alternative markings like direct value printing or manufacturer-specific codes.