Use solid core wire in the range of 22 to 26 AWG. This range provides good grip in the contact springs without putting excessive force on them. Very thin wire (28 AWG or finer) may not make reliable contact; wire that is too thick (20 AWG or heavier) can damage the contacts over time.

Pre-cut solid jumper wires such as ZipWire™ designed for breadboard use with machined pines are a convenient option and are available in a variety of lengths and colours . Use a colour-code system when you prototype to make circuits easier to debug. We like to use red for power, black for ground, and other colours for various signals.

Avoid stranded wire when prototyping on breadboards because the individual strands splay out and do not make reliable contact with the breadboard's spring clips. They can also break off inside the breadboard, causing intermittent faults that are difficult to trace.