diff --git a/src/renderer.typ b/src/renderer.typ
index 6070c3b..426a0a7 100644
--- a/src/renderer.typ
+++ b/src/renderer.typ
@@ -190,10 +190,15 @@
 
   if config.left-labels {
     // desc-x is the right edge of the label when they are on the left, so shift
-    // to its left edge: exactly the box width when wrapping, an estimate from
-    // the character count otherwise
+    // to its left edge
     txt-x -= if config.description-width == none {
-      range_.description.len() * config.default-font-size / 2pt
+      // the set rule in render is not in scope here, so measure the text with
+      // the font it will be drawn in
+      measure(text(
+        range_.description,
+        font: config.default-font-family,
+        size: config.default-font-size
+      )).width.pt()
     } else {
       config.description-width
     }