diff --git a/mlx/backend/cpu/arg_reduce.cpp b/mlx/backend/cpu/arg_reduce.cpp
index 41ab9fb60..3f42e7183 100644
--- a/mlx/backend/cpu/arg_reduce.cpp
+++ b/mlx/backend/cpu/arg_reduce.cpp
@@ -17,12 +17,12 @@ void arg_reduce(const array& in, array& out, const OpT& op, int axis) {
   Strides strides = remove_index(in.strides(), axis);
   Shape shape = remove_index(in.shape(), axis);
   auto in_ptr = in.data<InT>();
-  auto out_ptr = out.data<int64_t>();
+  auto out_ptr = out.data<uint32_t>();
 
   for (int64_t i = 0; i < out.size(); ++i) {
     auto loc = elem_to_loc(i, shape, strides);
     auto local_in_ptr = in_ptr + loc;
-    int64_t ind_v = 0;
+    uint32_t ind_v = 0;
     InT v = (*local_in_ptr);
     for (int64_t j = 0; j < axis_size; ++j, local_in_ptr += axis_stride) {
       op(j, (*local_in_ptr), &ind_v, &v);