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The apparent discrepancy between the value of the tensor-to-scalar ratioreported by the BICEP2 collaboration, $r = 0.20^{+0.07}_{-0.05}$ at 68% CL, andthe Planck upper limit, $r < 0.11$ at 95% CL, has attracted a great deal ofattention. In this short note, we show that this discrepancy is mainly due toan `apples to oranges' comparison. The result reported by BICEP2 was measuredat a pivot scale $k_* = 0.05$ Mpc$^{-1}$, assuming $n_t = 0$, whereas thePlanck limit was provided at $k_* = 0.002$ Mpc$^{-1}$, assuming the slow-rollconsistency relation $n_t = -r/8$. One should obviously compare the BICEP2 andPlanck results under the same circumstances. By imposing $n_t = 0$, the Planckconstraint at $k_* = 0.05$ Mpc$^{-1}$ becomes $r < 0.135$ at $95%$ CL, whichcan be compared directly with the BICEP2 result. Once a plausible dustcontribution to the BICEP2 signal is taken into account (DDM2 model), $r$ isreduced to $r = 0.16^{+0.06}_{-0.05}$ and the discrepancy becomes of order$1.3\sigma$ only.

A note of clarification: BICEP2 and Planck are not in tension