diff --git a/apps/web/src/services/alert-manager/v2/components/AlertsManagementTable.vue b/apps/web/src/services/alert-manager/v2/components/AlertsManagementTable.vue
index 74e95ca453..15cf2138e8 100644
--- a/apps/web/src/services/alert-manager/v2/components/AlertsManagementTable.vue
+++ b/apps/web/src/services/alert-manager/v2/components/AlertsManagementTable.vue
@@ -94,8 +94,8 @@ const state = reactive({
     refinedAlertList: computed<AlertModel[]>(() => storeState.alertList.map((alert) => ({
         ...alert,
         duration: alert.status === ALERT_STATUS.RESOLVED
-            ? calculateTime(alert?.resolved_at, storeState.timezone) || '0m'
-            : calculateTime(alert?.created_at, storeState.timezone) || '0m',
+            ? calculateTime(alert?.resolved_at, storeState.timezone)
+            : calculateTime(alert?.created_at, storeState.timezone),
         created_at: iso8601Formatter(alert.created_at, storeState.timezone),
         resolved_at: iso8601Formatter(alert.resolved_at, storeState.timezone) || '-',
     }))),
diff --git a/apps/web/src/services/alert-manager/v2/composables/alert-table-data.ts b/apps/web/src/services/alert-manager/v2/composables/alert-table-data.ts
index 1bf4d50b8b..7845e3ac25 100644
--- a/apps/web/src/services/alert-manager/v2/composables/alert-table-data.ts
+++ b/apps/web/src/services/alert-manager/v2/composables/alert-table-data.ts
@@ -4,8 +4,6 @@ import type { TranslateResult } from 'vue-i18n';
 
 import dayjs from 'dayjs';
 
-import { iso8601Formatter } from '@cloudforet/utils';
-
 import { ALERT_STATUS } from '@/schema/alert-manager/alert/constants';
 import type { AlertStatusType, AlertUrgencyType } from '@/schema/alert-manager/alert/type';
 import { i18n } from '@/translations';
@@ -46,24 +44,16 @@ export const alertStatusBadgeStyleTypeFormatter = (alertState) => {
 };
 
 export const calculateTime = (time: string, timezone: string): string => {
-    const today = dayjs().toISOString();
-    const createdTime = iso8601Formatter(time, timezone);
-    const todayTime = iso8601Formatter(today, timezone);
-    const timeForCalculate = dayjs(todayTime).diff(createdTime, 'minute');
-    const days = Math.floor((timeForCalculate / 1440) % 365);
-    const hours = Math.floor((timeForCalculate / 60) % 24);
-    const minutes = Math.floor(timeForCalculate % 60);
-    let result = '';
-
-    if (days > 0) {
-        result += `${days}d `;
-    }
-    if (hours > 0) {
-        result += `${hours}h `;
-    }
-    if (minutes > 0) {
-        result += `${minutes}m`;
-    }
-
-    return result.trim();
+    const createdTime = dayjs.tz(time, timezone);
+    const todayTime = dayjs().tz(timezone);
+    const timeForCalculate = todayTime.diff(createdTime, 'minute');
+    const days = Math.floor(timeForCalculate / 1440);
+    const hours = Math.floor((timeForCalculate % 1440) / 60);
+    const minutes = timeForCalculate % 60;
+    const parts: string[] = [];
+    if (days) parts.push(`${days}d`);
+    if (hours) parts.push(`${hours}h`);
+    if (minutes) parts.push(`${minutes}m`);
+
+    return parts.join(' ') || '0m';
 };