diff --git a/include/SDL_guid.h b/include/SDL_guid.h
index ba99f3ca2..b971636a0 100644
--- a/include/SDL_guid.h
+++ b/include/SDL_guid.h
@@ -67,7 +67,7 @@ typedef struct {
  * \param pszGUID buffer in which to write the ASCII string
  * \param cbGUID the size of pszGUID
  *
- * \since This function is available since SDL 2.tbd.
+ * \since This function is available since SDL 2.24.0.
  *
  * \sa SDL_GUIDFromString
  */
@@ -83,7 +83,7 @@ extern DECLSPEC void SDLCALL SDL_GUIDToString(SDL_GUID guid, char *pszGUID, int
  * \param pchGUID string containing an ASCII representation of a GUID
  * \returns a ::SDL_GUID structure.
  *
- * \since This function is available since SDL 2.tbd.
+ * \since This function is available since SDL 2.24.0.
  *
  * \sa SDL_GUIDToString
  */