diff --git a/cpp2rust/converter/converter.cpp b/cpp2rust/converter/converter.cpp
index 84b2e1ba..17eeece4 100644
--- a/cpp2rust/converter/converter.cpp
+++ b/cpp2rust/converter/converter.cpp
@@ -3088,7 +3088,7 @@ bool Converter::VisitOffsetOfExpr(clang::OffsetOfExpr *expr) {
     member_path += GetNamedDeclAsString(node.getField());
   }
   StrCat(
-      std::format("::std::mem::offset_of!({}, {}) as u64",
+      std::format("::std::mem::offset_of!({}, {})",
                   GetUnsafeTypeAsString(expr->getTypeSourceInfo()->getType()),
                   member_path));
   computed_expr_type_ = ComputedExprType::FreshValue;
diff --git a/tests/unit/out/unsafe/offsetof.rs b/tests/unit/out/unsafe/offsetof.rs
index fc9c6ad8..1562f269 100644
--- a/tests/unit/out/unsafe/offsetof.rs
+++ b/tests/unit/out/unsafe/offsetof.rs
@@ -31,10 +31,10 @@ pub fn main() {
     }
 }
 unsafe fn main_0() -> i32 {
-    assert!(((::std::mem::offset_of!(Layout, a) as u64) == (0_u64)));
-    assert!(((::std::mem::offset_of!(Layout, b) as u64) == (4_u64)));
-    assert!(((::std::mem::offset_of!(Layout, c) as u64) == (8_u64)));
-    assert!(((::std::mem::offset_of!(Outer, inner.y) as u64) == (8_u64)));
+    assert!(((::std::mem::offset_of!(Layout, a)) == (0_usize)));
+    assert!(((::std::mem::offset_of!(Layout, b)) == (4_usize)));
+    assert!(((::std::mem::offset_of!(Layout, c)) == (8_usize)));
+    assert!(((::std::mem::offset_of!(Outer, inner.y)) == (8_usize)));
     let mut v: Layout = Layout {
         a: 0_u8,
         b: 0_u32,
@@ -43,7 +43,7 @@ unsafe fn main_0() -> i32 {
     v.b = 3735928559_u32;
     let mut base: *mut u8 = ((&mut v as *mut Layout) as *mut u8);
     let mut bp: *mut u32 =
-        ((base.offset((::std::mem::offset_of!(Layout, b) as u64) as isize)) as *mut u32);
+        ((base.offset((::std::mem::offset_of!(Layout, b)) as isize)) as *mut u32);
     assert!(((*bp) == (3735928559_u32)));
     return 0;
 }