diff --git a/src/OpenClaw.Shared/Models.cs b/src/OpenClaw.Shared/Models.cs
index 15b1afb..44de5db 100644
--- a/src/OpenClaw.Shared/Models.cs
+++ b/src/OpenClaw.Shared/Models.cs
@@ -441,9 +441,9 @@ internal static class ModelFormatting
     {
         var delta = DateTime.UtcNow - timestampUtc;
         if (delta.TotalSeconds < 60) return "just now";
-        if (delta.TotalMinutes < 60) return $"{(int)Math.Round(delta.TotalMinutes)}m ago";
-        if (delta.TotalHours < 48) return $"{(int)Math.Round(delta.TotalHours)}h ago";
-        return $"{(int)Math.Round(delta.TotalDays)}d ago";
+        if (delta.TotalMinutes < 60) return $"{(int)delta.TotalMinutes}m ago";
+        if (delta.TotalHours < 48) return $"{(int)delta.TotalHours}h ago";
+        return $"{(int)delta.TotalDays}d ago";
     }
 
     /// <summary>
diff --git a/tests/OpenClaw.Shared.Tests/ModelsTests.cs b/tests/OpenClaw.Shared.Tests/ModelsTests.cs
index 3b5c68b..03b300f 100644
--- a/tests/OpenClaw.Shared.Tests/ModelsTests.cs
+++ b/tests/OpenClaw.Shared.Tests/ModelsTests.cs
@@ -762,6 +762,31 @@ public class SessionInfoAgeTextTests
         };
         Assert.Equal("10m ago", session.AgeText);
     }
+
+    [Fact]
+    public void AgeText_NearMinuteBoundary_DoesNotRoundUpTo60m()
+    {
+        // 59.5 minutes: Math.Round would produce 60 with banker's rounding;
+        // truncation correctly yields 59m ago.
+        var session = new SessionInfo { UpdatedAt = DateTime.UtcNow.AddSeconds(-3570) }; // 59.5 min
+        Assert.Equal("59m ago", session.AgeText);
+    }
+
+    [Fact]
+    public void AgeText_NearHourBoundary_DoesNotRoundUpTo48h()
+    {
+        // 47.5 hours: Math.Round would produce 48 with banker's rounding;
+        // truncation correctly yields 47h ago.
+        var session = new SessionInfo { UpdatedAt = DateTime.UtcNow.AddSeconds(-(int)(47.5 * 3600)) };
+        Assert.Equal("47h ago", session.AgeText);
+    }
+
+    [Fact]
+    public void AgeText_ExactlyOneMinute_ShowsMinutesAgo()
+    {
+        var session = new SessionInfo { UpdatedAt = DateTime.UtcNow.AddSeconds(-60) };
+        Assert.Equal("1m ago", session.AgeText);
+    }
 }
 
 public class SessionInfoRichDisplayTextTests