diff --git a/src/Flux.jl b/src/Flux.jl
index da040aa0..7b1fd800 100644
--- a/src/Flux.jl
+++ b/src/Flux.jl
@@ -8,7 +8,7 @@ using MacroTools: @forward
 
 export Chain, Dense, RNN, LSTM, GRU, Conv, MaxPool, MeanPool,
        DepthwiseConv, Dropout, LayerNorm, BatchNorm,
-       params, mapleaves, cpu, gpu
+       params, mapleaves, cpu, gpu, f32, f64
 
 @reexport using NNlib
 
diff --git a/src/treelike.jl b/src/treelike.jl
index bc1a5c0b..3d2b9185 100644
--- a/src/treelike.jl
+++ b/src/treelike.jl
@@ -1,4 +1,4 @@
-import Adapt: adapt
+import Adapt: adapt, adapt_storage
 import .Tracker: IdSet
 
 children(x) = ()
@@ -64,3 +64,22 @@ gpu_adaptor = identity
 end
 
 gpu(x) = mapleaves(gpu_adaptor, x)
+
+# Precision
+
+adapt_storage(T::Type{<:Real}, xs::AbstractArray{<:Real}) = convert.(T, xs)
+
+paramtype(T::Type{<:Real}, m) = mapleaves(x -> adapt(T, x), m)
+
+f32(m) = paramtype(Float32, m)
+f64(m) = paramtype(Float64, m)
+
+# General parameter map
+
+function mapparams(f, m)
+  mapleaves(m) do x
+    Tracker.istracked(x) ? param(f(Tracker.data(x))) :
+    x isa Union{AbstractArray,Number} ? f(x) :
+    x
+  end
+end
diff --git a/test/utils.jl b/test/utils.jl
index af0d50fe..c60645c6 100644
--- a/test/utils.jl
+++ b/test/utils.jl
@@ -86,3 +86,14 @@ end
   m = RNN(10, 5)
   @test size.(params(m)) == [(5, 10), (5, 5), (5,), (5,)]
 end
+
+@testset "Precision" begin
+  m = Chain(Dense(10, 5, relu), Dense(5, 2))
+  x = rand(10)
+  @test eltype(m[1].W.data) == Float32
+  @test eltype(m(x).data) == Float32
+  @test eltype(f64(m)(x).data) == Float64
+  @test eltype(f64(m)[1].W.data) == Float64
+  @test eltype(f32(f64(m))[1].W.data) == Float32
+  @test Tracker.isleaf(f32(f64(m))[1].W)
+end