diff --git a/plonky2/src/fri/validate_shape.rs b/plonky2/src/fri/validate_shape.rs
index 597adeda..0ef85c4c 100644
--- a/plonky2/src/fri/validate_shape.rs
+++ b/plonky2/src/fri/validate_shape.rs
@@ -6,6 +6,7 @@ use crate::fri::structure::FriInstanceInfo;
 use crate::fri::FriParams;
 use crate::hash::hash_types::RichField;
 use crate::plonk::config::GenericConfig;
+use crate::plonk::plonk_common::salt_size;
 
 pub(crate) fn validate_fri_proof_shape<F, C, const D: usize>(
     proof: &FriProof<F, C::Hasher, D>,
@@ -40,15 +41,7 @@ where
             .iter()
             .zip(&instance.oracles)
         {
-            ensure!(
-                leaf.len()
-                    == oracle.num_polys
-                        + if oracle.blinding && params.hiding {
-                            SALT_SIZE
-                        } else {
-                            0
-                        }
-            );
+            ensure!(leaf.len() == oracle.num_polys + salt_size(oracle.blinding && params.hiding));
             ensure!(merkle_proof.len() + cap_height == params.lde_bits());
         }