diff --git a/index.html b/index.html
index 96f1d1d..41c3250 100644
--- a/index.html
+++ b/index.html
@@ -531,6 +531,8 @@ <h2 class="ui header">Glyphs <em class="fontname" style="display: none;">FontNam
 
 function extractFont () {
   let data = $('#source').val()
+  
+  data = data.replace(/\bunsigned char\b/, "uint8_t")
 
   const bitmaps_part_re = /const\ uint8\_t\ (.*)Bitmaps\[\]/
   const glyph_part_re = /const\ GFXglyph/
@@ -1232,7 +1234,7 @@ <h2 class="ui header">Glyphs <em class="fontname" style="display: none;">FontNam
     })
 
     // Bitmaps
-    let bitmapsOutput = 'const uint8_t ' + name + 'Bitmaps[] PROGMEM = {\n'
+    let bitmapsOutput = 'const unsigned char ' + name + 'Bitmaps[] PROGMEM = {\n'
     // We want to join per 12 words
     const limit = Math.floor(bitsArray.length / 12)
     for (let nb = 0; nb < limit; nb++) {
@@ -1279,4 +1281,4 @@ <h2 class="ui header">Glyphs <em class="fontname" style="display: none;">FontNam
 })
 
 </script>
-</html>
\ No newline at end of file
+</html>