diff --git a/frontend/templates/index.html b/frontend/templates/index.html
index 366c7fd..79146c2 100644
--- a/frontend/templates/index.html
+++ b/frontend/templates/index.html
@@ -159,11 +159,11 @@ async function handleUpload(formData) {
     xhr.upload.addEventListener('progress', (e) => {
       console.log('upload', e.loaded, e.total, e.lengthComputable);
       if (e.lengthComputable) {
-        const pct = Math.round((e.loaded / e.total) * 100);
+        const pct = Math.max(1, Math.round((e.loaded / e.total) * 100));
         const mb = (e.loaded / (1024**2)).toFixed(0);
         const gb = (e.loaded / (1024**3)).toFixed(1);
         const size = e.loaded > 100*1024*1024 ? gb + ' GiB' : mb + ' MB';
-        setPhase('Uploading source file... ' + size, pct, false);
+        setPhase('Uploading source file... ' + size, pct, pct < 5);
       } else {
         const mb = (e.loaded / (1024**2)).toFixed(0);
         setPhase('Uploading source file... ' + mb + ' MB', 0, true);