diff --git a/frontend/src/components/cards/CardIListtem.tsx b/frontend/src/components/cards/CardIListtem.tsx
index f56cac2..443e3f1 100644
--- a/frontend/src/components/cards/CardIListtem.tsx
+++ b/frontend/src/components/cards/CardIListtem.tsx
@@ -1,5 +1,5 @@
 import type { Card } from '@/client/types.gen'
-import { stripHtml } from '@/utils/text'
+import { stripHtml } from '@/utils/textUtils'
 import { Box, HStack, IconButton, Text } from '@chakra-ui/react'
 import { Link } from '@tanstack/react-router'
 import { useTranslation } from 'react-i18next'
diff --git a/frontend/src/components/commonUI/GuestModeNotice.tsx b/frontend/src/components/commonUI/GuestModeNotice.tsx
index b30f114..195edce 100644
--- a/frontend/src/components/commonUI/GuestModeNotice.tsx
+++ b/frontend/src/components/commonUI/GuestModeNotice.tsx
@@ -1,4 +1,4 @@
-import { useAuthContext } from '@/hooks/useAuthContext'
+import { useAuthContext } from '@/contexts/useAuthContext'
 import { HStack, Text } from '@chakra-ui/react'
 import { useNavigate } from '@tanstack/react-router'
 import { useTranslation } from 'react-i18next'
diff --git a/frontend/src/components/commonUI/Navbar.tsx b/frontend/src/components/commonUI/Navbar.tsx
index 836e4d6..4ee26ff 100644
--- a/frontend/src/components/commonUI/Navbar.tsx
+++ b/frontend/src/components/commonUI/Navbar.tsx
@@ -1,5 +1,5 @@
 import Logo from '@/assets/Logo.svg'
-import { useAuthContext } from '@/hooks/useAuthContext'
+import { useAuthContext } from '@/contexts/useAuthContext'
 import { Flex, IconButton, Image } from '@chakra-ui/react'
 import { Link } from '@tanstack/react-router'
 import { useState } from 'react'
diff --git a/frontend/src/components/commonUI/TextCounter.tsx b/frontend/src/components/commonUI/TextCounter.tsx
index 047492d..8289a21 100644
--- a/frontend/src/components/commonUI/TextCounter.tsx
+++ b/frontend/src/components/commonUI/TextCounter.tsx
@@ -1,4 +1,4 @@
-import { MAX_CHARACTERS, WARNING_THRESHOLD } from '@/utils/text'
+import { MAX_CHARACTERS, WARNING_THRESHOLD } from '@/utils/textUtils'
 import { Text } from '@chakra-ui/react'
 
 interface TextCounterProps {
diff --git a/frontend/src/components/stats/StatsSummaryGrid.tsx b/frontend/src/components/stats/StatsSummaryGrid.tsx
index 58961e8..9266a89 100644
--- a/frontend/src/components/stats/StatsSummaryGrid.tsx
+++ b/frontend/src/components/stats/StatsSummaryGrid.tsx
@@ -2,7 +2,7 @@ import { Box, SimpleGrid, Text } from '@chakra-ui/react'
 import { useTranslation } from 'react-i18next'
 
 import type { CollectionBasicInfo, PracticeSessionStats } from '@/client'
-import { calculateAverageAccuracy, calculateLearningTrend } from '@/utils/stats'
+import { calculateAverageAccuracy, calculateLearningTrend } from '@/utils/statsUtils'
 
 interface StatCardProps {
   label: string
diff --git a/frontend/src/hooks/useAuthContext.tsx b/frontend/src/contexts/useAuthContext.tsx
similarity index 100%
rename from frontend/src/hooks/useAuthContext.tsx
rename to frontend/src/contexts/useAuthContext.tsx
diff --git a/frontend/src/hooks/useAuth.ts b/frontend/src/hooks/useAuth.ts
index 6192eba..ce111e2 100644
--- a/frontend/src/hooks/useAuth.ts
+++ b/frontend/src/hooks/useAuth.ts
@@ -1,11 +1,13 @@
+import { useAuthContext } from '@/contexts/useAuthContext'
 import { useMutation, useQuery, useQueryClient } from '@tanstack/react-query'
 import { useNavigate } from '@tanstack/react-router'
 import { useState } from 'react'
 import { useTranslation } from 'react-i18next'
-import { useAuthContext } from './useAuthContext'
 
+import type { ApiRequestOptions } from '@/client/core/ApiRequestOptions'
 import { toaster } from '@/components/ui/toaster'
-import { AxiosError } from 'axios'
+import { type ErrorResponse, handleError, mapToApiError } from '@/utils/errorsUtils'
+import type { AxiosError } from 'axios'
 import {
   type Body_login_login_access_token as AccessToken,
   LoginService,
@@ -14,13 +16,6 @@ import {
   UsersService,
 } from '../client'
 
-interface ErrorResponse {
-  body: {
-    detail?: string
-  }
-  status?: number
-}
-
 const useAuth = () => {
   const { t } = useTranslation()
   const [error, setError] = useState<string | null>(null)
@@ -45,22 +40,19 @@ const useAuth = () => {
       })
     },
     onError: (err: Error | AxiosError | ErrorResponse) => {
-      const errDetail =
-        err instanceof AxiosError
-          ? err.message
-          : 'body' in err && typeof err.body === 'object' && err.body
-            ? String(err.body.detail) || t('general.errors.somethingWentWrong')
-            : t('general.errors.somethingWentWrong')
-      toaster.create({
-        title: t('general.errors.errorCreatingAccount'),
-        description: errDetail,
-        type: 'error',
+      const request: ApiRequestOptions = {
+        method: 'POST',
+        url: '/signup',
+      }
+      const apiErrorDto = mapToApiError(err, request)
+      const message = handleError(apiErrorDto, {
+        toastTitle: t('general.errors.errorCreatingAccount'),
       })
-      const status = (err as AxiosError).status ?? (err as ErrorResponse).status
-      if (status === 409) {
+
+      if (apiErrorDto.status === 409) {
         setError(t('general.errors.emailAlreadyInUse') || t('general.errors.somethingWentWrong'))
       } else {
-        setError(errDetail)
+        setError(message)
       }
     },
     onSettled: () => {
@@ -81,22 +73,20 @@ const useAuth = () => {
       navigate({ to: '/collections' })
     },
     onError: (err: Error | AxiosError | ErrorResponse) => {
-      const errDetail =
-        err instanceof AxiosError
-          ? err.message
-          : 'body' in err && typeof err.body === 'object' && err.body
-            ? String(err.body.detail) || t('general.errors.somethingWentWrong')
-            : t('general.errors.somethingWentWrong')
-
-      const finalError = Array.isArray(errDetail)
-        ? t('general.errors.invalidCredentials')
-        : errDetail
-
-      toaster.create({
-        title: t('general.errors.loginFailed'),
-        description: finalError,
-        type: 'error',
+      const request: ApiRequestOptions = {
+        method: 'POST',
+        url: '/login',
+      }
+      const apiErrorDto = mapToApiError(err, request)
+      const message = handleError(apiErrorDto, {
+        toastTitle: t('general.errors.loginFailed'),
+        fallbackMessage: t('general.errors.somethingWentWrong'),
       })
+
+      let finalError = message
+      if (apiErrorDto.status === 401) {
+        finalError = t('general.errors.invalidCredentials')
+      }
       setError(finalError)
     },
   })
diff --git a/frontend/src/hooks/useTextCounter.tsx b/frontend/src/hooks/useTextCounter.tsx
index 3135cdc..52fbed1 100644
--- a/frontend/src/hooks/useTextCounter.tsx
+++ b/frontend/src/hooks/useTextCounter.tsx
@@ -1,5 +1,5 @@
 import { toaster } from '@/components/ui/toaster'
-import { MAX_CHARACTERS } from '@/utils/text'
+import { MAX_CHARACTERS } from '@/utils/textUtils'
 import type { Editor } from '@tiptap/react'
 import { useCallback, useEffect, useRef } from 'react'
 import { useTranslation } from 'react-i18next'
diff --git a/frontend/src/main.tsx b/frontend/src/main.tsx
index 5b0e7bd..d0789c3 100644
--- a/frontend/src/main.tsx
+++ b/frontend/src/main.tsx
@@ -1,5 +1,6 @@
 import './i18n'
 import { ColorModeProvider } from '@/components/ui/color-mode'
+import { AuthProvider } from '@/contexts/useAuthContext'
 import { ChakraProvider } from '@chakra-ui/react'
 import { MutationCache, QueryCache, QueryClient, QueryClientProvider } from '@tanstack/react-query'
 import { RouterProvider, createRouter } from '@tanstack/react-router'
@@ -7,7 +8,6 @@ import { StrictMode } from 'react'
 import ReactDOM from 'react-dom/client'
 import { ApiError, OpenAPI } from './client'
 import AnalyticsConsent from './components/commonUI/AnalyticsConsent'
-import { AuthProvider } from './hooks/useAuthContext'
 import { routeTree } from './routeTree.gen'
 import { system } from './theme'
 
diff --git a/frontend/src/routes/_publicLayout/index.tsx b/frontend/src/routes/_publicLayout/index.tsx
index 1073ae0..5634cd8 100644
--- a/frontend/src/routes/_publicLayout/index.tsx
+++ b/frontend/src/routes/_publicLayout/index.tsx
@@ -1,7 +1,7 @@
 import { BlueButton, DefaultButton } from '@/components/commonUI/Button'
 import { Footer } from '@/components/commonUI/Footer'
 import { useColorMode } from '@/components/ui/color-mode'
-import { useAuthContext } from '@/hooks/useAuthContext'
+import { useAuthContext } from '@/contexts/useAuthContext'
 import { Container, Heading, Image, Stack, Text, VStack } from '@chakra-ui/react'
 import { Link, createFileRoute, useNavigate } from '@tanstack/react-router'
 import { useTranslation } from 'react-i18next'
diff --git a/frontend/src/routes/_publicLayout/login.tsx b/frontend/src/routes/_publicLayout/login.tsx
index d9cfbc3..4122394 100644
--- a/frontend/src/routes/_publicLayout/login.tsx
+++ b/frontend/src/routes/_publicLayout/login.tsx
@@ -1,5 +1,6 @@
 import Logo from '@/assets/Logo.svg'
 import useAuth from '@/hooks/useAuth'
+import { emailPattern } from '@/utils/patternsUtils'
 import { Container, Field, Fieldset, Image, Text } from '@chakra-ui/react'
 import { Link, createFileRoute, redirect } from '@tanstack/react-router'
 import { type SubmitHandler, useForm } from 'react-hook-form'
@@ -7,7 +8,6 @@ import { useTranslation } from 'react-i18next'
 import type { Body_login_login_access_token as AccessToken } from '../../client'
 import { DefaultButton } from '../../components/commonUI/Button'
 import { DefaultInput } from '../../components/commonUI/Input'
-import { emailPattern } from '../../utils'
 
 export const Route = createFileRoute('/_publicLayout/login')({
   component: Login,
diff --git a/frontend/src/routes/_publicLayout/signup.tsx b/frontend/src/routes/_publicLayout/signup.tsx
index d7671b9..746a024 100644
--- a/frontend/src/routes/_publicLayout/signup.tsx
+++ b/frontend/src/routes/_publicLayout/signup.tsx
@@ -1,5 +1,7 @@
 import Logo from '@/assets/Logo.svg'
 import useAuth from '@/hooks/useAuth'
+import { emailPattern } from '@/utils/patternsUtils'
+import { confirmPasswordRules, passwordRules } from '@/utils/rulesUtils'
 import { Button, Container, Field, Fieldset, Image, Text } from '@chakra-ui/react'
 import { Link, createFileRoute, redirect } from '@tanstack/react-router'
 import { type SubmitHandler, useForm } from 'react-hook-form'
@@ -7,7 +9,6 @@ import { useTranslation } from 'react-i18next'
 import type { UserRegister } from '../../client'
 import { DefaultInput } from '../../components/commonUI/Input'
 import PasswordInput from '../../components/commonUI/PasswordInput'
-import { confirmPasswordRules, emailPattern, passwordRules } from '../../utils'
 
 export const Route = createFileRoute('/_publicLayout/signup')({
   component: SignUp,
diff --git a/frontend/src/utils.ts b/frontend/src/utils.ts
deleted file mode 100644
index e748a2e..0000000
--- a/frontend/src/utils.ts
+++ /dev/null
@@ -1,73 +0,0 @@
-import type { ApiError } from './client'
-import i18n, { i18nPromise } from './i18n'
-
-let t: (key: string) => string = () => ''
-
-i18nPromise.then(() => {
-  t = i18n.t.bind(i18n)
-})
-
-export const emailPattern = {
-  value: /^[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,}$/i,
-  message: t('general.errors.invalidEmail'),
-}
-
-export const namePattern = {
-  value: /^[A-Za-z\s\u00C0-\u017F]{1,30}$/,
-  message: t('general.errors.invalidName'),
-}
-
-export const passwordRules = (isRequired = true) => {
-  const rules: {
-    minLength: { value: number; message: string }
-    required?: string
-  } = {
-    minLength: {
-      value: 8,
-      message: t('general.errors.passwordMinCharacters'),
-    },
-  }
-
-  if (isRequired) {
-    rules.required = t('general.errors.passwordIsRequired')
-  }
-
-  return rules
-}
-
-export const confirmPasswordRules = (getValues: () => unknown, isRequired = true) => {
-  const rules: {
-    validate: (value: string) => boolean | string
-    required?: string
-  } = {
-    validate: (value: string) => {
-      const formValues = getValues() as {
-        password?: string
-        new_password?: string
-      }
-      const password = formValues.password || formValues.new_password
-      return value === password ? true : t('general.errors.passwordsDoNotMatch')
-    },
-  }
-
-  if (isRequired) {
-    rules.required = t('general.errors.passwordConfirmationIsRequired')
-  }
-
-  return rules
-}
-
-export const handleError = (
-  err: ApiError,
-  showToast: (title: string, message: string, type: string) => void,
-) => {
-  const errDetail = (err.body as { detail?: string | { msg: string }[] })?.detail
-  let errorMessage = t('general.errors.default')
-
-  if (typeof errDetail === 'string') {
-    errorMessage = errDetail
-  } else if (Array.isArray(errDetail) && errDetail.length > 0) {
-    errorMessage = errDetail[0].msg
-  }
-  showToast(t('general.errors.error'), errorMessage, 'error')
-}
diff --git a/frontend/src/utils/errorsUtils.ts b/frontend/src/utils/errorsUtils.ts
new file mode 100644
index 0000000..4d8a52b
--- /dev/null
+++ b/frontend/src/utils/errorsUtils.ts
@@ -0,0 +1,94 @@
+import { ApiError } from '@/client'
+import type { ApiRequestOptions } from '@/client/core/ApiRequestOptions'
+import type { ApiResult } from '@/client/core/ApiResult'
+import { toaster } from '@/components/ui/toaster'
+import { translate } from '@/utils/translationUtils'
+import type { AxiosError } from 'axios'
+
+type ToastType = 'error' | 'success' | 'info' | 'warning'
+
+export const handleError = (
+  err: ApiError,
+  options?: {
+    toastTitle?: string
+    toastType?: ToastType
+    fallbackMessage?: string
+    silent?: boolean
+  },
+): string => {
+  const errDetail = (err.body as { detail?: string | { msg: string }[] })?.detail
+  let errorMessage = options?.fallbackMessage || translate('general.errors.default')
+
+  if (typeof errDetail === 'string') {
+    errorMessage = errDetail
+  } else if (Array.isArray(errDetail) && errDetail.length > 0) {
+    errorMessage = errDetail[0].msg
+  }
+
+  if (!options?.silent) {
+    toaster.create({
+      title: options?.toastTitle || translate('general.errors.error'),
+      description: errorMessage,
+      type: options?.toastType || 'error',
+    })
+  }
+
+  return errorMessage
+}
+
+export interface ErrorResponse {
+  body: {
+    detail?: string
+  }
+  status?: number
+}
+
+export function mapToApiError(
+  err: Error | AxiosError | ErrorResponse,
+  request: ApiRequestOptions,
+): ApiError {
+  let url = ''
+  let status = 0
+  let statusText = ''
+  let body: unknown = {}
+  let message = 'Unexpected error'
+
+  switch (true) {
+    case 'isAxiosError' in err && (err as AxiosError).isAxiosError: {
+      const axiosErr = err as AxiosError
+      url = axiosErr.config?.url ?? ''
+      status = axiosErr.response?.status ?? 404
+      statusText = axiosErr.response?.statusText ?? ''
+      body = axiosErr.response?.data ?? {}
+      message = axiosErr.message
+      break
+    }
+    case 'body' in err: {
+      const errorResponse = err as ErrorResponse
+      url = request.url
+      status = errorResponse.status ?? 404
+      statusText = ''
+      body = errorResponse.body
+      message = errorResponse.body?.detail ?? 'Unknown error'
+      break
+    }
+    default: {
+      url = request.url
+      status = 404
+      statusText = ''
+      body = {}
+      message = err.message
+      break
+    }
+  }
+
+  const response: ApiResult = {
+    url,
+    status,
+    statusText,
+    body,
+    ok: status === 200,
+  }
+
+  return new ApiError(request, response, message)
+}
diff --git a/frontend/src/utils/patternsUtils.ts b/frontend/src/utils/patternsUtils.ts
new file mode 100644
index 0000000..87b752d
--- /dev/null
+++ b/frontend/src/utils/patternsUtils.ts
@@ -0,0 +1,11 @@
+import { translate } from '@/utils/translationUtils'
+
+export const emailPattern = {
+  value: /^[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,}$/i,
+  message: translate('general.errors.invalidEmail'),
+}
+
+export const namePattern = {
+  value: /^[A-Za-z\s\u00C0-\u017F]{1,30}$/,
+  message: translate('general.errors.invalidName'),
+}
diff --git a/frontend/src/utils/rulesUtils.ts b/frontend/src/utils/rulesUtils.ts
new file mode 100644
index 0000000..c44764e
--- /dev/null
+++ b/frontend/src/utils/rulesUtils.ts
@@ -0,0 +1,41 @@
+import { translate } from '@/utils/translationUtils'
+
+export const passwordRules = (isRequired = true) => {
+  const rules: {
+    minLength: { value: number; message: string }
+    required?: string
+  } = {
+    minLength: {
+      value: 8,
+      message: translate('general.errors.passwordMinCharacters'),
+    },
+  }
+
+  if (isRequired) {
+    rules.required = translate('general.errors.passwordIsRequired')
+  }
+
+  return rules
+}
+
+export const confirmPasswordRules = (getValues: () => unknown, isRequired = true) => {
+  const rules: {
+    validate: (value: string) => boolean | string
+    required?: string
+  } = {
+    validate: (value: string) => {
+      const formValues = getValues() as {
+        password?: string
+        new_password?: string
+      }
+      const password = formValues.password || formValues.new_password
+      return value === password ? true : translate('general.errors.passwordsDoNotMatch')
+    },
+  }
+
+  if (isRequired) {
+    rules.required = translate('general.errors.passwordConfirmationIsRequired')
+  }
+
+  return rules
+}
diff --git a/frontend/src/utils/stats.ts b/frontend/src/utils/statsUtils.ts
similarity index 100%
rename from frontend/src/utils/stats.ts
rename to frontend/src/utils/statsUtils.ts
diff --git a/frontend/src/utils/text.ts b/frontend/src/utils/textUtils.ts
similarity index 100%
rename from frontend/src/utils/text.ts
rename to frontend/src/utils/textUtils.ts
diff --git a/frontend/src/utils/translationUtils.ts b/frontend/src/utils/translationUtils.ts
new file mode 100644
index 0000000..c6f38dc
--- /dev/null
+++ b/frontend/src/utils/translationUtils.ts
@@ -0,0 +1,7 @@
+import i18n, { i18nPromise } from '@/i18n'
+
+export let translate: (key: string) => string = () => ''
+
+i18nPromise.then(() => {
+  translate = i18n.t.bind(i18n)
+})