About this tool
Plant Spacing Calculator is a free, in-browser tool that works out how many plants fit in a rectangular garden bed. Enter the bed's length and width in feet, the spacing between plants in a row and the spacing between rows in inches, and pick a layout — it returns the total plant count plus rows, plants per row and density per square foot. Nothing is uploaded; the math runs on your device.
The number of rows is floor(bed width × 12 ÷ row spacing) and plants per row is floor(bed length × 12 ÷ plant spacing), converting feet to inches so both spacings share units. For a square grid, total = rows × plants per row. A triangular (offset) layout staggers every other row so plants nest closer, fitting about 15.5% more, so total = floor(grid total × 1.155). Plants per square foot is the total divided by the bed area.
Use the square grid for beds you walk and weed in straight lines, and the triangular layout to squeeze more plants into intensive or square-foot beds. Read the spacing from the back of the seed packet — it is usually given as inches between plants and inches between rows.