diff --git a/src/serde/deserialize_program.rs b/src/serde/deserialize_program.rs
index 713ef1eda3..382795f48e 100644
--- a/src/serde/deserialize_program.rs
+++ b/src/serde/deserialize_program.rs
@@ -6,6 +6,7 @@ use crate::{
     },
 };
 use felt::{Felt, FeltOps, PRIME_STR};
+use num_traits::Num;
 use serde::{de, de::MapAccess, de::SeqAccess, Deserialize, Deserializer};
 use serde_json::Number;
 use std::{collections::HashMap, fmt, io::Read};
@@ -191,12 +192,7 @@ impl<'de> de::Visitor<'de> for FeltVisitor {
         if let Some(no_prefix_hex) = value.strip_prefix("0x") {
             // Add padding if necessary
             let no_prefix_hex = deserialize_utils::maybe_add_padding(no_prefix_hex.to_string());
-            let decoded_result: Result<Vec<u8>, hex::FromHexError> = hex::decode(no_prefix_hex);
-
-            match decoded_result {
-                Ok(decoded_hex) => Ok(Felt::from_bytes_be(&decoded_hex)),
-                Err(e) => Err(e).map_err(de::Error::custom),
-            }
+            Ok(Felt::from_str_radix(&no_prefix_hex, 16).map_err(de::Error::custom)?)
         } else {
             Err(String::from("hex prefix error")).map_err(de::Error::custom)
         }
@@ -222,14 +218,9 @@ impl<'de> de::Visitor<'de> for MaybeRelocatableVisitor {
             if let Some(no_prefix_hex) = value.strip_prefix("0x") {
                 // Add padding if necessary
                 let no_prefix_hex = deserialize_utils::maybe_add_padding(no_prefix_hex.to_string());
-                let decoded_result: Result<Vec<u8>, hex::FromHexError> = hex::decode(no_prefix_hex);
-
-                match decoded_result {
-                    Ok(decoded_hex) => {
-                        data.push(MaybeRelocatable::Int(Felt::from_bytes_be(&decoded_hex)))
-                    }
-                    Err(e) => return Err(e).map_err(de::Error::custom),
-                };
+                data.push(MaybeRelocatable::Int(
+                    Felt::from_str_radix(&no_prefix_hex, 16).map_err(de::Error::custom)?,
+                ));
             } else {
                 return Err(String::from("hex prefix error")).map_err(de::Error::custom);
             };