Seed Spacing Calculator — Within a Row
Find within-row spacing from a chosen position density and row spacing, with centimetre, metre, inch and foot results.
Work backward from a chosen planting-position density to the required distance between seeds along each row. Enter the row-centre spacing and the density you want to lay out. The answer is shown in centimetres, metres, inches and feet so you can compare it with your planter or garden measurements.
How to use this tool
- Choose a target density of planting positions and its area unit.
- Enter the distance between row centres.
- Select the unit for that known distance.
- Read the solved spacing and check it against the practical layout.
Formula
Within-row spacing = 1 / (positions per square metre × row spacing in metres)
The two perpendicular distances define one rectangular cell per position. Density and the known distance must both be positive. An acre uses the international foot, not the retired US survey-foot definition. All displayed distances describe the same result.
Example
A target of 10 positions/m² with rows 50 cm apart gives 1 ÷ (10 × 0.5) = 0.2 m, or 20 cm between seeds. Multiplying 0.5 m by 0.2 m checks the 0.1 m² cell area.
Frequently asked questions
Is this the best spacing for my crop?
It is the geometry for your supplied target. Crop variety, canopy, disease pressure, equipment and growing conditions determine whether that layout is appropriate; the calculator does not optimize those factors.
Should I enter seeds or final plants as the target?
Enter the positions to be placed. If the target is an established plant population, first determine the sowing density using an appropriate emergence estimate. Otherwise the result assumes every position produces a surviving plant.
Does it handle staggered rows or multiple seeds per hole?
No. The formula assumes one position per rectangular cell and uniform row spacing. Clustered sowing, alternating wide and narrow rows, triangular layouts and field-edge counts require a different explicit layout.
Sources
Last updated: 2026