diff --git a/library/core/src/fmt/mod.rs b/library/core/src/fmt/mod.rs
index 8e1d5d1ae62..a3b907df8ee 100644
--- a/library/core/src/fmt/mod.rs
+++ b/library/core/src/fmt/mod.rs
@@ -277,7 +277,7 @@ pub enum Sign {
 pub enum DebugAsHex {
     /// Use lower-case hexadecimal integers for the `Debug` trait (like [the `x?` type](../../std/fmt/index.html#formatting-traits)).
     Lower,
-    /// Use upper-case hexadecimal integers for the `Debug` trait (like [the `x?` type](../../std/fmt/index.html#formatting-traits)).
+    /// Use upper-case hexadecimal integers for the `Debug` trait (like [the `X?` type](../../std/fmt/index.html#formatting-traits)).
     Upper,
 }