diff --git a/src/layers/normalise.jl b/src/layers/normalise.jl
index 1adc3050..3755f3fc 100644
--- a/src/layers/normalise.jl
+++ b/src/layers/normalise.jl
@@ -29,7 +29,7 @@ _dropout_kernel(y::T, p, q) where {T} = y > p ? T(1 / q) : T(0)
 
 function dropout(x, p; dims = :)
   istraining() || return x
-  y = similar(x)
+  y = similar(x, _dropout_shape(x, dims))
   rand!(y)
   y .= _dropout_kernel.(y, p, 1 - p)
   return x .* y