diff --git a/master_changes.md b/master_changes.md
index 45b56deb343..c38ca7d6816 100644
--- a/master_changes.md
+++ b/master_changes.md
@@ -204,6 +204,7 @@ users)
 
 ## opam-core
   * `OpamStd.List.split`: Improve performance [#6210 @kit-ty-kate]
+  * `OpamStd.Char`: Create the module and export `is_whitespace` [#5492 @kit-ty-kate]
   * `OpamStd.Sys.{get_terminal_columns,uname,getconf,guess_shell_compat}`: Harden the process calls to account for failures [#6230 @kit-ty-kate - fix #6215]
   * `OpamStd.Sys.getconf`: was removed, replaced by `get_long_bit` [#6217 @kit-ty-kate]
   * `OpamStd.Sys.get_long_bit`: was added, which returns the output of the `getconf LONG_BIT` command [#6217 @kit-ty-kate]
diff --git a/src/core/opamStd.ml b/src/core/opamStd.ml
index 2b766533742..14a6ef3f975 100644
--- a/src/core/opamStd.ml
+++ b/src/core/opamStd.ml
@@ -550,7 +550,15 @@ module Option = struct
   end
 end
 
+module OpamChar = struct
 
+  (* TODO: Replace by Stdlib.Char.Ascii.is_space
+     (to be introduced in OCaml 5.4) *)
+  let is_whitespace = function
+    | ' ' | '\t' | '\r' | '\n' -> true
+    | _ -> false
+
+end
 
 module OpamString = struct
 
@@ -630,26 +638,22 @@ module OpamString = struct
     for i = 0 to len - 1 do Bytes.set b i (f s.[i]) done;
     Bytes.to_string b
 
-  let is_whitespace = function
-    | ' ' | '\t' | '\r' | '\n' -> true
-    | _ -> false
-
   let strip str =
     let p = ref 0 in
     let l = String.length str in
-    while !p < l && is_whitespace (String.unsafe_get str !p) do
+    while !p < l && OpamChar.is_whitespace (String.unsafe_get str !p) do
       incr p;
     done;
     let p = !p in
     let l = ref (l - 1) in
-    while !l >= p && is_whitespace (String.unsafe_get str !l) do
+    while !l >= p && OpamChar.is_whitespace (String.unsafe_get str !l) do
       decr l;
     done;
     String.sub str p (!l - p + 1)
 
   let strip_right str =
     let rec aux i =
-      if i < 0 || not (is_whitespace str.[i]) then i else aux (i-1)
+      if i < 0 || not (OpamChar.is_whitespace str.[i]) then i else aux (i-1)
     in
     let l = String.length str in
     let i = aux (l-1) in
@@ -1898,6 +1902,7 @@ module Config = struct
 end
 
 module List = OpamList
+module Char = OpamChar
 module String = OpamString
 module Sys = OpamSys
 module Format = OpamFormat
diff --git a/src/core/opamStd.mli b/src/core/opamStd.mli
index 74b06acb2de..7680d56bffd 100644
--- a/src/core/opamStd.mli
+++ b/src/core/opamStd.mli
@@ -260,6 +260,12 @@ module List : sig
   val fold_left_map: ('s -> 'a -> ('s * 'b)) -> 's -> 'a list -> 's * 'b list
 end
 
+module Char : sig
+
+  val is_whitespace : char -> bool
+
+end
+
 module String : sig
 
   (** {3 Collections} *)