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Buck

Example D = 41.67% — L ≥ 19.44 µH, Cout ≥ 1.5 µF — inductor carries 1 A average, 1.15 A peak (ripple 300 mA)

$D=\frac{V_{\mathrm{out}}}{V_{\mathrm{in}}}$ and $L=\frac{(V_{\mathrm{in}}-V_{\mathrm{out}})D}{\Delta I_L{f}_{\mathrm{sw}}}$. Continuous conduction with ideal switches — a real design lands a few percent higher on duty once the switch and diode drops are counted.

Boost

Example D = 58.33% — L ≥ 16.2 µH, Cout ≥ 11.67 µF — inductor carries 1.2 A average, 1.38 A peak (ripple 360 mA)

$D=1-\frac{V_{\mathrm{in}}}{V_{\mathrm{out}}}$ and $L=\frac{V_{\mathrm{in}}D}{\Delta I_L{f}_{\mathrm{sw}}}$. Continuous conduction with ideal switches — a real design lands a few percent higher on duty once the switch and diode drops are counted.