diff --git a/crates/blockifier/src/execution/contract_class.rs b/crates/blockifier/src/execution/contract_class.rs
index 6641c81fce..e80512407b 100644
--- a/crates/blockifier/src/execution/contract_class.rs
+++ b/crates/blockifier/src/execution/contract_class.rs
@@ -22,7 +22,7 @@ use semver::Version;
 use serde::de::Error as DeserializationError;
 use serde::{Deserialize, Deserializer, Serialize};
 use starknet_api::contract_class::{ContractClass, EntryPointType};
-use starknet_api::core::EntryPointSelector;
+use starknet_api::core::{EntryPointSelector, WORD_WIDTH};
 use starknet_api::deprecated_contract_class::{
     ContractClass as DeprecatedContractClass,
     EntryPointOffset,
@@ -514,6 +514,76 @@ fn convert_entry_points_v1(external: &[CasmContractEntryPoint]) -> Vec<EntryPoin
         .collect()
 }
 
+#[derive(Clone, Debug)]
+// TODO(Ayelet,10/02/2024): Change to bytes.
+pub struct ClassInfo {
+    contract_class: ContractClass,
+    sierra_program_length: usize,
+    abi_length: usize,
+}
+
+impl TryFrom<starknet_api::contract_class::ClassInfo> for ClassInfo {
+    type Error = ProgramError;
+
+    fn try_from(class_info: starknet_api::contract_class::ClassInfo) -> Result<Self, Self::Error> {
+        let starknet_api::contract_class::ClassInfo {
+            contract_class,
+            sierra_program_length,
+            abi_length,
+        } = class_info;
+
+        Ok(Self { contract_class: contract_class.clone(), sierra_program_length, abi_length })
+    }
+}
+
+impl ClassInfo {
+    pub fn bytecode_length(&self) -> usize {
+        match &self.contract_class {
+            ContractClass::V0(contract_class) => contract_class.bytecode_length(),
+            ContractClass::V1(contract_class) => contract_class.bytecode.len(),
+        }
+    }
+
+    pub fn contract_class(&self) -> ContractClass {
+        self.contract_class.clone()
+    }
+
+    pub fn sierra_program_length(&self) -> usize {
+        self.sierra_program_length
+    }
+
+    pub fn abi_length(&self) -> usize {
+        self.abi_length
+    }
+
+    pub fn code_size(&self) -> usize {
+        (self.bytecode_length() + self.sierra_program_length())
+            // We assume each felt is a word.
+            * WORD_WIDTH
+            + self.abi_length()
+    }
+
+    pub fn new(
+        contract_class: &ContractClass,
+        sierra_program_length: usize,
+        abi_length: usize,
+    ) -> ContractClassResult<Self> {
+        let (contract_class_version, condition) = match contract_class {
+            ContractClass::V0(_) => (0, sierra_program_length == 0),
+            ContractClass::V1(_) => (1, sierra_program_length > 0),
+        };
+
+        if condition {
+            Ok(Self { contract_class: contract_class.clone(), sierra_program_length, abi_length })
+        } else {
+            Err(ContractClassError::ContractClassVersionSierraProgramLengthMismatch {
+                contract_class_version,
+                sierra_program_length,
+            })
+        }
+    }
+}
+
 // TODO(Yoni): organize this file.
 #[derive(Clone, Debug, Default, Eq, PartialEq)]
 /// Modelled after [cairo_lang_starknet_classes::contract_class::ContractEntryPoints].
diff --git a/crates/blockifier/src/fee/eth_gas_constants.rs b/crates/blockifier/src/fee/eth_gas_constants.rs
index e01eb73132..0055c5d1f4 100644
--- a/crates/blockifier/src/fee/eth_gas_constants.rs
+++ b/crates/blockifier/src/fee/eth_gas_constants.rs
@@ -1,8 +1,8 @@
+use starknet_api::core::WORD_WIDTH;
+
 // Calldata.
 pub const GAS_PER_MEMORY_ZERO_BYTE: usize = 4;
 pub const GAS_PER_MEMORY_BYTE: usize = 16;
-// TODO(AvivG): use starknet_api::core::WORD_WIDTH instead.
-pub const WORD_WIDTH: usize = 32;
 pub const GAS_PER_MEMORY_WORD: usize = GAS_PER_MEMORY_BYTE * WORD_WIDTH;
 
 // Blob Data.
diff --git a/crates/blockifier/src/fee/receipt_test.rs b/crates/blockifier/src/fee/receipt_test.rs
index 95c315918b..ac1a72e24d 100644
--- a/crates/blockifier/src/fee/receipt_test.rs
+++ b/crates/blockifier/src/fee/receipt_test.rs
@@ -1,4 +1,5 @@
 use rstest::{fixture, rstest};
+use starknet_api::core::WORD_WIDTH;
 use starknet_api::execution_resources::GasVector;
 use starknet_api::transaction::fields::GasVectorComputationMode;
 use starknet_api::transaction::L2ToL1Payload;
@@ -85,8 +86,7 @@ fn test_calculate_tx_gas_usage_basic<'a>(
             .gas_per_code_byte;
         let code_gas_cost = (gas_per_code_byte
             * u64_from_usize(
-                (class_info.bytecode_length() + class_info.sierra_program_length())
-                    * eth_gas_constants::WORD_WIDTH
+                (class_info.bytecode_length() + class_info.sierra_program_length()) * WORD_WIDTH
                     + class_info.abi_length(),
             ))
         .to_integer()