diff --git a/app/components/app/patient/entry-form.vue b/app/components/app/patient/entry-form.vue
index 4f577091..7b6c578f 100644
--- a/app/components/app/patient/entry-form.vue
+++ b/app/components/app/patient/entry-form.vue
@@ -5,6 +5,9 @@ import { toTypedSchema } from '@vee-validate/zod'
 // types
 import { type PatientFormData, PatientSchema } from '~/schemas/patient.schema'
 
+// utils
+import { calculateAge } from '~/models/person'
+
 // components
 import * as DE from '~/components/pub/my-ui/doc-entry'
 import { InputBase, FileField as FileUpload } from '~/components/pub/my-ui/form'
@@ -26,7 +29,9 @@ import {
   SelectReligion,
 } from './fields'
 
-interface FormData extends PatientFormData {}
+interface FormData extends PatientFormData {
+  _calculatedAge: string
+}
 
 // Type untuk initial values (sebelum transform schema)
 interface PatientFormInput {
@@ -74,6 +79,18 @@ defineExpose({
   setValues,
   values,
 })
+
+watch(
+  () => values.birthDate,
+  (newValue) => {
+    if (newValue) {
+      setFieldValue('_calculatedAge', calculateAge(newValue))
+    }
+  },
+  {
+    immediate: true,
+  },
+)
 </script>
 
 <template>
@@ -140,6 +157,13 @@ defineExpose({
         is-required
         :is-disabled="isReadonly"
       />
+      <InputBase
+        field-name="_calculatedAge"
+        label="Usia"
+        placeholder="-"
+        numeric-only
+        is-disabled
+      />
       <SelectEducation
         field-name="education"
         label="Pendidikan"
diff --git a/app/components/app/patient/fields/select-dob.vue b/app/components/app/patient/fields/select-dob.vue
index 985eb046..81d18940 100644
--- a/app/components/app/patient/fields/select-dob.vue
+++ b/app/components/app/patient/fields/select-dob.vue
@@ -1,16 +1,15 @@
 <script setup lang="ts">
-import type { FormErrors } from '~/types/error'
-import { differenceInDays, differenceInMonths, differenceInYears, parseISO } from 'date-fns'
-import { Input } from '~/components/pub/ui/input'
+import { calculateAge } from '~/models/person'
 import { cn } from '~/lib/utils'
 
+// componenets
 import * as DE from '~/components/pub/my-ui/doc-entry'
+import { Input } from '~/components/pub/ui/input'
 
 const props = defineProps<{
   fieldName?: string
   label?: string
   placeholder?: string
-  errors?: FormErrors
   class?: string
   selectClass?: string
   fieldGroupClass?: string
@@ -23,56 +22,13 @@ const {
   fieldName = 'birthDate',
   label = 'Tanggal Lahir',
   placeholder = 'Pilih tanggal lahir',
-  errors,
   class: containerClass,
   fieldGroupClass,
   labelClass,
 } = props
 
 // Reactive variables for age calculation
-const patientAge = ref<string>('Masukkan tanggal lahir')
-
-// Function to calculate age with years, months, and days
-function calculateAge(birthDate: string | Date | undefined): string {
-  if (!birthDate) {
-    return 'Masukkan tanggal lahir'
-  }
-
-  try {
-    let dateObj: Date
-
-    if (typeof birthDate === 'string') {
-      dateObj = parseISO(birthDate)
-    } else {
-      dateObj = birthDate
-    }
-
-    const today = new Date()
-
-    // Calculate years, months, and days
-    const totalYears = differenceInYears(today, dateObj)
-
-    // Calculate remaining months after years
-    const yearsPassed = new Date(dateObj)
-    yearsPassed.setFullYear(yearsPassed.getFullYear() + totalYears)
-    const remainingMonths = differenceInMonths(today, yearsPassed)
-
-    // Calculate remaining days after years and months
-    const monthsPassed = new Date(yearsPassed)
-    monthsPassed.setMonth(monthsPassed.getMonth() + remainingMonths)
-    const remainingDays = differenceInDays(today, monthsPassed)
-
-    // Format the result
-    const parts = []
-    if (totalYears > 0) parts.push(`${totalYears} Tahun`)
-    if (remainingMonths > 0) parts.push(`${remainingMonths} Bulan`)
-    if (remainingDays > 0) parts.push(`${remainingDays} Hari`)
-
-    return parts.length > 0 ? parts.join(' ') : '0 Hari'
-  } catch {
-    return 'Masukkan tanggal lahir'
-  }
-}
+const patientAge = ref<string>('-')
 </script>
 
 <template>
@@ -86,7 +42,6 @@ function calculateAge(birthDate: string | Date | undefined): string {
     </DE.Label>
     <DE.Field
       :id="fieldName"
-      :errors="errors"
       :class="cn('select-field-wrapper')"
     >
       <FormField
@@ -116,27 +71,4 @@ function calculateAge(birthDate: string | Date | undefined): string {
       </FormField>
     </DE.Field>
   </DE.Cell>
-  <DE.Cell>
-    <DE.Label label-for="patientAge">Usia</DE.Label>
-    <DE.Field id="patientAge">
-      <FormField name="patientAge">
-        <FormItem>
-          <FormControl>
-            <Input
-              :value="patientAge"
-              disabled
-              readonly
-              placeholder="Masukkan tanggal lahir"
-              :class="
-                cn(
-                  'cursor-not-allowed bg-gray-50 focus:border-primary focus:ring-2 focus:ring-primary focus:ring-offset-0',
-                )
-              "
-            />
-          </FormControl>
-          <FormMessage />
-        </FormItem>
-      </FormField>
-    </DE.Field>
-  </DE.Cell>
 </template>
diff --git a/app/components/app/patient/preview.vue b/app/components/app/patient/preview.vue
index a4fec2e2..1c5d822a 100644
--- a/app/components/app/patient/preview.vue
+++ b/app/components/app/patient/preview.vue
@@ -19,6 +19,7 @@ import {
   religionCodes,
 } from '~/lib/constants'
 import { mapToComboboxOptList } from '~/lib/utils'
+import { calculateAge } from '~/models/person'
 
 // components
 import { Accordion, AccordionContent, AccordionItem, AccordionTrigger } from '~/components/pub/ui/accordion'
@@ -64,14 +65,7 @@ const patientAge = computed(() => {
   if (!props.patient.person.birthDate) {
     return '-'
   }
-  const birthDate = new Date(props.patient.person.birthDate)
-  const today = new Date()
-  let age = today.getFullYear() - birthDate.getFullYear()
-  const monthDiff = today.getMonth() - birthDate.getMonth()
-  if (monthDiff < 0 || (monthDiff === 0 && today.getDate() < birthDate.getDate())) {
-    age--
-  }
-  return age
+  return calculateAge(props.patient.person.birthDate)
 })
 // #endregion
 
@@ -117,7 +111,7 @@ function onNavigate(type: ClickType) {
                 : '-'
             }}
           </DetailRow>
-          <DetailRow label="Usia">{{ patientAge || '-' }} Tahun</DetailRow>
+          <DetailRow label="Usia">{{ patientAge || '-' }}</DetailRow>
           <DetailRow label="Tanggal Daftar">
             {{
               patient.person.createdAt
diff --git a/app/models/person.ts b/app/models/person.ts
index c257e1a1..f7130d31 100644
--- a/app/models/person.ts
+++ b/app/models/person.ts
@@ -1,3 +1,5 @@
+import { differenceInDays, differenceInMonths, differenceInYears, parseISO } from 'date-fns'
+
 import { type Base, genBase } from './_base'
 import type { PersonAddress } from './person-address'
 import type { PersonContact } from './person-contact'
@@ -56,3 +58,44 @@ export function parseName(person: Person): string {
 
   return fullName
 }
+
+export function calculateAge(birthDate: string | Date | undefined): string {
+  if (!birthDate) {
+    return 'Masukkan tanggal lahir'
+  }
+
+  try {
+    let dateObj: Date
+
+    if (typeof birthDate === 'string') {
+      dateObj = parseISO(birthDate)
+    } else {
+      dateObj = birthDate
+    }
+
+    const today = new Date()
+
+    // Calculate years, months, and days
+    const totalYears = differenceInYears(today, dateObj)
+
+    // Calculate remaining months after years
+    const yearsPassed = new Date(dateObj)
+    yearsPassed.setFullYear(yearsPassed.getFullYear() + totalYears)
+    const remainingMonths = differenceInMonths(today, yearsPassed)
+
+    // Calculate remaining days after years and months
+    const monthsPassed = new Date(yearsPassed)
+    monthsPassed.setMonth(monthsPassed.getMonth() + remainingMonths)
+    const remainingDays = differenceInDays(today, monthsPassed)
+
+    // Format the result
+    const parts = []
+    if (totalYears > 0) parts.push(`${totalYears} Tahun`)
+    if (remainingMonths > 0) parts.push(`${remainingMonths} Bulan`)
+    if (remainingDays > 0) parts.push(`${remainingDays} Hari`)
+
+    return parts.length > 0 ? parts.join(' ') : '0 Hari'
+  } catch {
+    return 'Masukkan tanggal lahir'
+  }
+}