diff --git a/cache.h b/cache.h
index 29ed24b802..db02a2de7f 100644
--- a/cache.h
+++ b/cache.h
@@ -1213,7 +1213,7 @@ extern const char *pager_program;
 extern int pager_in_use(void);
 extern int pager_use_color;
 extern int term_columns(void);
-extern int decimal_width(int);
+extern int decimal_width(uintmax_t);
 extern int check_pager_config(const char *cmd);
 
 extern const char *editor_program;
diff --git a/pager.c b/pager.c
index fa19765eb9..314210351b 100644
--- a/pager.c
+++ b/pager.c
@@ -139,12 +139,12 @@ int term_columns(void)
 /*
  * How many columns do we need to show this number in decimal?
  */
-int decimal_width(int number)
+int decimal_width(uintmax_t number)
 {
-	int i, width;
+	int width;
 
-	for (width = 1, i = 10; i <= number; width++)
-		i *= 10;
+	for (width = 1; number >= 10; width++)
+		number /= 10;
 	return width;
 }