Design Tools
Find the optimal resistors to use for a resistor divider, or find which combination of resistors (series or parallel) is closest to your target resistance.
Developed in the 1920s by the Radio Manufacturers Association, color codes are used to denote the value of resistors using colored bands. Use this chart to convert values to and from the color coding system.
Use this in-browser javascript circuit simulator to see the voltage and flow of current in your circuits. Learn about electronics by seeing how they work.
Use this chart to find the best-sized holes for drilling tap and clearance holes for Imperial threads. Sizes are given in decimal and American drill sizes.
Use this chart to find the best-sized holes for drilling tap and clearance holes for Metric threads. Sizes are given in decimal and American drill sizes.