diff --git a/fonts.js b/fonts.js
index 307393fa4..a7fb509d0 100755
--- a/fonts.js
+++ b/fonts.js
@@ -1033,7 +1033,7 @@ var Font = (function Font() {
             var index = firstCode;
             for (var j = start; j <= end; j++) {
               var code = j - firstCode - 1;
-              var mapping = encoding[index + 1] || {};
+              var mapping = encoding[index] || {};
               mapping.unicode = glyphs[code].unicode;
               encoding[index++] = mapping;
             }