← All categoriesTHE TOOLBOXEngineering tools2 free tools for engineering. Run these tools in your browser without an account.Resistor color-code decoderRead a conventional 4-, 5- or 6-band axial resistor code.DC LED series-resistor plannerChoose an E12 or E24 series resistor from nominal low-voltage DC inputs.Filter this category by task, audience or timing →