The number of path lights you need will depend on the size and layout of your outdoor space, as well as your goals for the lighting. As a general rule, path lights should be placed in a way that provides adequate lighting along the entire pathway, without creating too much glare or shadow.
One common guideline when determining the number of path lights needed for a specific area is to space them 6 to 8 feet apart. So, if you have a 40-foot walkway, you would need about 5 to 7 path lights for optimal illumination.