diff --git a/public/scripts/reasoning.js b/public/scripts/reasoning.js
index 34922313d..0f19dd548 100644
--- a/public/scripts/reasoning.js
+++ b/public/scripts/reasoning.js
@@ -80,7 +80,8 @@ export function extractReasoningFromData(data) {
 export function updateReasoningTimeUI(element, duration, { forceEnd = false } = {}) {
     if (duration) {
         const durationStr = moment.duration(duration).locale(getCurrentLocale()).humanize({ s: 50, ss: 9 });
-        element.textContent = t`Thought for ${durationStr}`;
+        const secondsStr = moment.duration(duration).asSeconds();
+        element.innerHTML = t`Thought for <span title="${secondsStr} seconds">${durationStr}</span>`;
     } else if (forceEnd) {
         element.textContent = t`Thought for some time`;
     } else {