Superconductivity in the topological non-trivial Dirac semimetal PdTe$_2$ was recently shown to be type-I. We here report measurements of the relative magnetic penetration depth, $ Delta lambda$, on several single crystals using a high precision tunnel diode oscillator technique. The temperature variation $Delta lambda (T)$ follows an exponential function for $T/T_c < 0.4$, consistent with a fully-gapped superconducting state and weak or moderately coupling superconductivity. By fitting the data we extract a $lambda (0)$-value of $sim 500$~nm. The normalized superfluid density is in good agreement with the computed curve for a type-I superconductor with nonlocal electrodynamics. Small steps are observed in $Delta lambda (T)$, which possibly relates to a locally lower $T_c$ due to defects in the single crystalline sample. single crystalline sample.
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