[en] Superconductivity in the topological non-trivial Dirac semimetal PdTe₂ was recently shown to be type-I. We hereby report measurements of the relative magnetic penetration depth, , on several single crystals using a high precision tunnel diode oscillator technique. The temperature variation follows an exponential function for , consistent with a fully-gapped superconducting state and weak or moderately coupling superconductivity. By fitting the data we extract a -value of  ∼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 , which possibly relates to a locally lower due to defects in the single crystalline sample. (paper)