diff --git a/const-oid/src/encoder.rs b/const-oid/src/encoder.rs
index c901e492a..3edbbf6aa 100644
--- a/const-oid/src/encoder.rs
+++ b/const-oid/src/encoder.rs
@@ -132,7 +132,7 @@ const fn base128_byte(arc: Arc, pos: usize, total: usize) -> Result<u8> {
     debug_assert!(pos < total);
     let last_byte = checked_add!(pos, 1) == total;
     let mask = if last_byte { 0 } else { 0b10000000 };
-    let shift = checked_sub!(checked_sub!(total, pos), 1) * 7;
+    let shift = checked_mul!(checked_sub!(checked_sub!(total, pos), 1), 7);
     Ok(((arc >> shift) & 0b1111111) as u8 | mask)
 }