I disagree with the statement above.

Spring rate, for a coil spring, is determined/defined by the following three characteristics:

1. Diameter of the wire (or cross-sectional value of the wire). In simple terms, when the wire diameter increases, spring rate increases.

2. Mean Diameter of the spring (mean diameter, or OD of the spring minus the wire diameter). When the mean diameter of a spring increases, the spring rate decreases.

3. Number of active coils. In general, active coils are calculated as two (2) less than the total number of coils as the first coil on each end of a spring is, in layman's terms, not of use, or in-active. As the number of coils decreases, the spring rate increases.

Regards,
Joe