resistor-calculator.com

resistor-calculator.com is a browser-based tool for decoding resistor color bands. Select the color code, read the resistance value - supports 3-, 4-, 5- and 6-band resistors including tolerance and temperature coefficient. Additionally, a LED series resistor calculator helps size LED circuits safely.

• Color code calculator for 3-, 4-, 5- and 6-band resistors incl. tolerance and TCR
• Visual color band selection with instant resistance value calculation
• LED series resistor calculator: R = (Vs - Vf) / If with E-series standard values
• Automatic suggestions for LED parameters (forward voltage by color)
• Power dissipation calculation and safety-oriented sizing recommendations
• Live calculation without page reload, multilingual interface
• Use cases: prototyping, repair, education and DIY electronics