Color Ring Resistor Calculator

Decode resistor color bands instantly according to IEC 60062 standard. Interactive resistor drawing, tolerance, TC (ppm/°C), and reverse engineering from resistance value.

?️ 1kΩ (5%) ? 10kΩ (1%) ⚡ 220Ω (5%) ? 4.7kΩ (1%) ? 100kΩ (5%)
Note: Digit bands (first 2 or 3 rings) accept Black through White only. Gold and Silver are used exclusively as multiplier or tolerance rings.
Resistance: 0 Ω
±0%
Temp.coeff: —
Reading direction: For axial resistors, hold the tolerance band (gold/silver) to the right side. 4‑band: digit, digit, multiplier, tolerance. 5‑band: 3 digits, multiplier, tolerance. 6‑band adds temperature coefficient (ppm/K).
Color bands update live with selection
Reverse Lookup: Resistance → Color Bands
Converts resistance to the nearest standard color code combination (E24/E96 approximations). Tolerance band set to Brown (±1%) for precision or Gold (±5%).
For non‑standard resistance values, the tool returns the closest E‑series match.
Privacy: All calculations performed locally in your browser — no data transmission.

Understanding Resistor Color Codes

The color-ring code (IEC 60062) is a worldwide standard for marking the resistance value, tolerance, and temperature coefficient on small electronic components. Developed in the 1920s by the Radio Manufacturers Association (RMA) and later standardized, it helps engineers and hobbyists quickly identify resistor values without additional test equipment.

Standard Color Digit Chart

Color Digit Multiplier Tolerance Temp. Coeff. (ppm/K)
Black 0 ×10⁰ — —
Brown 1 ×10¹ ±1% 100
Red 2 ×10² ±2% 50
Orange 3 ×10³ ±0.05% 15
Yellow 4 ×10⁴ ±0.02% 25
Green 5 ×10⁵ ±0.5% 20
Blue 6 ×10⁶ ±0.25% 10
Violet 7 ×10⁷ ±0.1% 5
Grey 8 ×10⁸ ±0.01% 1
White 9 ×10⁹ — —
Gold — ×0.1 ±5% —
Silver — ×0.01 ±10% —

How to Read Bands

  • 4-band resistors: Two significant digits, multiplier, tolerance. E.g., Brown-Black-Red-Gold → 10 × 100 = 1kΩ ±5%.
  • 5-band resistors: Three significant digits, multiplier, tolerance – high precision (1% or 2%).
  • 6-band resistors: Same as 5‑band plus temperature coefficient (ppm/°C) for precision circuits.
  • Multiplier band: Gold (×0.1) and Silver (×0.01) used for low resistance values.
E-series standards: Resistors follow preferred numbers (E6, E12, E24, E96). Our reverse lookup matches the closest standard value based on significant digits.

Why Use This Interactive Resistor Tool?

  • ✅ Visual live drawing – Resistor graphic updates colors instantly, reducing reading errors.
  • ✅ Educational deep-dive: Learn tolerance, TC, and decoding strategies.
  • ✅ Reverse engineering: Enter any resistance, and the tool suggests matching color bands (4/5/6 band).
  • ✅ Electronics labs & repair: Quickly identify unknown resistors without lookup tables.
Real-world application: power supply repair

In switch-mode power supplies, a burnt resistor often has unreadable bands. By measuring the remaining intact portion or using schematic values, you can reverse-calculate the required resistance. With our reverse lookup, input 2.2kΩ, select 5‑band, and instantly get Red-Red-Black-Brown-Brown (2.2kΩ ±1%). Perfect for restoration projects.

Frequently Asked Questions

4-band: standard 5% or 10% tolerance; 5-band: high precision (1%, 2% etc) with three significant digits; 6-band: adds temp coefficient for critical applications like oscillators or precision measurement.

Gold and silver serve as multipliers (0.1 and 0.01) for low resistance values under 10 ohms, making them compactly coded.

The reverse algorithm computes the closest standard color code based on significant digits and E-series approximation. For most common E12/E24/E96 values it returns accurate bands; highly specific non-standard values may return nearest match.

For general LEDs, pull-ups – no. For analog sensors, oscillators, or low-drift designs, a low TC (blue/violet) ensures stable resistance across temperature changes.
Standards & references: IEC 60062:2016 Marking codes for resistors and capacitors; ANSI/EIA-196; “The Art of Electronics” by Horowitz & Hill; EIA RS-279. This calculator implements precise decoding logic validated against MIL-STD-1285.

Engineer-grade reliability – Developed with electronic engineering best practices. Field-tested by repair technicians and students worldwide. Source color mapping based on official resistor color code tables from leading manufacturers (Vishay, Yageo, Bourns). Updated March 2025.