HPLC Column Efficiency (N)

Determine theoretical plates to assess chromatographic column performance.

Retention Time (tr) [min]

Peak Width at Base (W) [min]

Or: Peak Width at Half-Max (W½) [min]

Column Length (L) [cm]

Theoretical Plates (N)

Plate Height (HETP) [mm]

0.00

Equations: If Base Width ($W$) is used: $N = 16(t_r/W)^2$. If Half-Max Width ($W_{1/2}$) is used: $N = 5.54(t_r/W_{1/2})^2$. HETP = $(L/N) \times 10$ (to convert cm to mm). Lower HETP values indicate a more efficient column.