diff --git a/lib/pure/terminal.nim b/lib/pure/terminal.nim
index de96293f8ac5..4177eb002ad8 100644
--- a/lib/pure/terminal.nim
+++ b/lib/pure/terminal.nim
@@ -305,7 +305,7 @@ else:
 
     var w: int
     var s = getEnv("COLUMNS") # Try standard env var
-    if len(s) > 0 and parseInt(s, w) > 0 and w > 0:
+    if len(s) > 0 and parseSaturatedNatural(s, w) > 0 and w > 0:
       return w
     w = terminalWidthIoctl([0, 1, 2]) # Try standard file descriptors
     if w > 0: return w
@@ -339,7 +339,7 @@ else:
 
     var h: int
     var s = getEnv("LINES") # Try standard env var
-    if len(s) > 0 and parseInt(s, h) > 0 and h > 0:
+    if len(s) > 0 and parseSaturatedNatural(s, h) > 0 and h > 0:
       return h
     h = terminalHeightIoctl([0, 1, 2]) # Try standard file descriptors
     if h > 0: return h