diff --git a/server/app/static/device_status_bar.js b/server/app/static/device_status_bar.js
index 79657ea..3c53b79 100644
--- a/server/app/static/device_status_bar.js
+++ b/server/app/static/device_status_bar.js
@@ -26,9 +26,16 @@ function renderDeviceStatusBar(device) {
   }
   if (device.battery) {
     rows.push(['Battery', `${device.battery.percent}%`, false]);
-  }
-  if (device.battery_estimate_s !== null && device.battery_estimate_s !== undefined) {
-    rows.push(['Est. battery life left', `~${formatDuration(device.battery_estimate_s)}`, false]);
+    // Shown as soon as there's any battery reading at all, even before
+    // battery_estimate_s can compute a rate (needs 2h+ span and a 2%+
+    // drop within the current discharge cycle -- see common.py) -- so
+    // it's clear the number is coming, not that the feature is broken.
+    const hasEstimate = device.battery_estimate_s !== null && device.battery_estimate_s !== undefined;
+    rows.push([
+      'Est. battery life left',
+      hasEstimate ? `~${formatDuration(device.battery_estimate_s)}` : 'Not enough data yet',
+      false,
+    ]);
   }
   for (const [label, value, alert] of rows) {
     const stat = document.createElement('span');