diff --git a/package.json b/package.json
index e51db5bc..9185d341 100644
--- a/package.json
+++ b/package.json
@@ -46,5 +46,12 @@
       "last 1 firefox version",
       "last 1 safari version"
     ]
+  },
+  "jest": {
+    "collectCoverageFrom": [
+      "src/**/*.{js,jsx,ts,tsx}",
+      "!src/index.tsx",
+      "!src/test-utils/*"
+    ]
   }
 }
\ No newline at end of file
diff --git a/src/App.test.tsx b/src/App.test.tsx
index 838df452..893840e3 100644
--- a/src/App.test.tsx
+++ b/src/App.test.tsx
@@ -1,7 +1,13 @@
-import { render } from "@testing-library/react";
+import { render, screen } from "@testing-library/react";
 
 import App from "./App";
+import { Provider } from 'react-redux';
+import { store } from './store';
 
-test("renders learn react link", () => {
-  render(<App />);
+test("renders App.tsx", () => {
+    render(<Provider store={store}>
+        <App/>
+    </Provider>);
+    // screen.debug();
+    // expect(true).toBe(true)
 });
diff --git a/src/components/Todo/Todo.test.tsx b/src/components/Todo/Todo.test.tsx
new file mode 100644
index 00000000..b2a3df13
--- /dev/null
+++ b/src/components/Todo/Todo.test.tsx
@@ -0,0 +1,18 @@
+import Todo from './Todo';
+import { render, screen } from '@testing-library/react';
+
+describe('<Todo />', () => {
+    it('should render done mark when done is false', () => {
+        render(<Todo title={'TODO_TITLE'} done={false}/>)
+        const title = screen.getByText('TODO_TITLE')
+        expect(title.classList.contains('done')).toBe(false)
+        screen.getByText('Done')
+    })
+
+    it('should render undone mark when done is true', () => {
+        render(<Todo title={'TODO_TITLE'} done={true}/>)
+        const title = screen.getByText('TODO_TITLE')
+        expect(title.classList.contains('done')).toBe(true)
+        screen.getByText('Undone')
+    })
+})
\ No newline at end of file
diff --git a/src/components/TodoDetail/TodoDetail.test.tsx b/src/components/TodoDetail/TodoDetail.test.tsx
new file mode 100644
index 00000000..0754a587
--- /dev/null
+++ b/src/components/TodoDetail/TodoDetail.test.tsx
@@ -0,0 +1,52 @@
+import { Provider } from 'react-redux';
+import { TodoState } from '../../store/slices/todo';
+import { getMockStore } from '../../test-utils/mock';
+import { MemoryRouter } from 'react-router';
+import { Navigate, Route, Routes } from 'react-router-dom';
+import TodoDetail from './TodoDetail';
+import { render, screen } from '@testing-library/react';
+import axios from 'axios';
+
+const stubInitialState: TodoState = {
+    todos: [
+        { id: 3, title: 'TODO_TEST_TITLE_3', content: 'TODO_TEST_CONTENT_3', done: false },
+    ],
+    selectedTodo: null,
+}
+
+const mockStore = getMockStore({ todo: stubInitialState })
+
+describe('<TodoDetail/>', () => {
+    let todoDetail: JSX.Element = (
+        <Provider store={mockStore}>
+            <MemoryRouter>
+                <Routes>
+                    <Route path='/todo-detail/:id' element={<TodoDetail />} />
+                    <Route path='*' element={<Navigate to={'/todo-detail/3'} />} />
+                </Routes>
+            </MemoryRouter>
+        </Provider>
+    )
+
+    it('should render TodoDetail', async () => {
+        jest.spyOn(axios, 'get').mockImplementation(() => {
+            return Promise.resolve({
+                data: {
+                    id: 3,
+                    title: 'TODO_TEST_TITLE_3',
+                    content: 'TODO_TEST_CONTENT_3',
+                    done: false,
+                },
+            })
+        })
+        render(todoDetail)
+        await screen.findByText('TODO_TEST_TITLE_3')
+        await screen.findByText('TODO_TEST_CONTENT_3')
+    })
+
+    it('should not render if there is no todo', async () => {
+        render(todoDetail)
+        jest.spyOn(axios, 'get').mockImplementationOnce(() => Promise.reject())
+        expect(screen.queryAllByText('TODO_TEST_TITLE_3')).toHaveLength(0)
+    })
+})
diff --git a/src/containers/TodoList/NewTodo/NewTodo.test.tsx b/src/containers/TodoList/NewTodo/NewTodo.test.tsx
new file mode 100644
index 00000000..69b825c8
--- /dev/null
+++ b/src/containers/TodoList/NewTodo/NewTodo.test.tsx
@@ -0,0 +1,96 @@
+import { fireEvent, render, screen, waitFor } from '@testing-library/react';
+import NewTodo from './NewTodo';
+import axios from 'axios';
+import * as todoSlice from "../../../store/slices/todo";
+import { Provider } from 'react-redux';
+import { MemoryRouter } from 'react-router';
+import { Navigate, Route, Routes } from 'react-router-dom';
+import TodoDetail from '../../../components/TodoDetail/TodoDetail';
+import { getMockStore } from '../../../test-utils/mock';
+import { TodoState } from '../../../store/slices/todo';
+
+const mockNavigate = jest.fn()
+jest.mock('react-router', () => ({
+    ...jest.requireActual('react-router'),
+    Navigate: (props: any) => {
+        mockNavigate(props.to);
+        return null;
+    },
+    useNavigate: () => mockNavigate,
+}))
+
+const stubInitialState: TodoState = {
+    todos: [],
+    selectedTodo: null,
+}
+
+const mockStore = getMockStore({ todo: stubInitialState })
+
+describe('<NewTodo/>', () => {
+    let todoDetail: JSX.Element = (
+        <Provider store={mockStore}>
+            <NewTodo/>
+        </Provider>
+    )
+
+    it('should render without errors', () => {
+        render(todoDetail)
+        screen.getByText('Add a Todo')
+    })
+    it('should render title input', () => {
+        render(todoDetail)
+        screen.getByLabelText('Title')
+    })
+    it('should render content input', () => {
+        render(todoDetail)
+        screen.getByLabelText('Content')
+    })
+    it('should render submit button', () => {
+        render(todoDetail)
+        screen.getByText('Submit')
+    })
+    it('should render navigate to /todos when submitted', async () => {
+        jest.spyOn(axios, 'post').mockResolvedValueOnce({
+            data: {
+                id: 1,
+                title: 'TITLE',
+                content: 'CONTENT',
+                done: false,
+            },
+        })
+        render(todoDetail)
+        const titleInput = screen.getByLabelText('Title')
+        const contentInput = screen.getByLabelText('Content')
+        const submitButton = screen.getByText('Submit')
+        fireEvent.change(titleInput, { target: { value: 'TITLE' }})
+        fireEvent.change(contentInput, { target: { value: 'CONTENT' }})
+        await screen.findByDisplayValue('TITLE')
+        await screen.findByDisplayValue('CONTENT')
+        fireEvent.click(submitButton)
+
+        await waitFor(() => expect(mockNavigate).toHaveBeenCalledWith('/todos'))
+    })
+    it('should alert error when submitted', async () => {
+        const mockPostTodo = jest.spyOn(todoSlice, 'postTodo')
+        window.alert = jest.fn()
+        console.error = jest.fn()
+        jest.spyOn(axios, 'post').mockRejectedValueOnce(new Error('ERROR'))
+
+        render(todoDetail)
+        const titleInput = screen.getByLabelText('Title')
+        const contentInput = screen.getByLabelText('Content')
+        const submitButton = screen.getByText('Submit')
+        fireEvent.change(titleInput, { target: { value: 'TITLE' }})
+        fireEvent.change(contentInput, { target: { value: 'CONTENT' }})
+        await screen.findByDisplayValue('TITLE')
+        await screen.findByDisplayValue('CONTENT')
+        fireEvent.click(submitButton)
+
+        expect(mockPostTodo).toHaveBeenCalledWith({
+            title: 'TITLE',
+            content: 'CONTENT',
+        })
+        await waitFor(() => expect(mockNavigate).not.toHaveBeenCalled())
+        await waitFor(() => expect(window.alert).toHaveBeenCalledWith('Error on post Todo'))
+    })
+})
diff --git a/src/containers/TodoList/TodoList.test.tsx b/src/containers/TodoList/TodoList.test.tsx
new file mode 100644
index 00000000..74344361
--- /dev/null
+++ b/src/containers/TodoList/TodoList.test.tsx
@@ -0,0 +1,99 @@
+import { IProps as TodoProps } from "../../components/Todo/Todo"
+import { TodoState } from '../../store/slices/todo';
+import { getMockStore } from '../../test-utils/mock';
+import { Provider } from 'react-redux';
+import { MemoryRouter } from 'react-router';
+import { Route, Routes } from 'react-router-dom';
+import TodoList from './TodoList';
+import { fireEvent, render, screen } from '@testing-library/react';
+import exp from 'constants';
+
+jest.mock('../../components/Todo/Todo', () => (props: TodoProps) => (
+    <div data-testid="spyTodo">
+        <div className="title" onClick={props.clickDetail}>
+            {props.title}
+        </div>
+        <button className="doneButton" onClick={props.clickDone}>
+            done
+        </button>
+        <button className="deleteButton" onClick={props.clickDelete}>
+            delete
+        </button>
+    </div>
+))
+
+const stubInitialState: TodoState = {
+    todos: [
+        { id: 1, title: "TODO_TEST_TITLE_1", content: "TODO_TEST_CONTENT_1", done: false },
+        { id: 2, title: "TODO_TEST_TITLE_2", content: "TODO_TEST_CONTENT_2", done: false },
+        { id: 3, title: "TODO_TEST_TITLE_3", content: "TODO_TEST_CONTENT_3", done: false },
+    ],
+    selectedTodo: null,
+}
+
+const mockStore = getMockStore({ todo: stubInitialState })
+
+const mockNavigate = jest.fn()
+jest.mock('react-router', () => ({
+    ...jest.requireActual('react-router'),
+    useNavigate: () => mockNavigate,
+}))
+
+const mockDispatch = jest.fn()
+jest.mock('react-redux', () => ({
+    ...jest.requireActual('react-redux'),
+    useDispatch: () => mockDispatch,
+}))
+
+describe('<TodoList/>', () => {
+    let todoList: JSX.Element
+    beforeEach(() => {
+        jest.clearAllMocks()
+        todoList = (
+            <Provider store={mockStore}>
+                <MemoryRouter>
+                    <Routes>
+                        <Route path="/" element={<TodoList title="TODOLIST_TEST_TITLE" />} />
+                    </Routes>
+                </MemoryRouter>
+            </Provider>
+        )
+    })
+
+    it('should render TodoList', () => {
+        const { container } = render(todoList)
+        expect(container).toBeTruthy()
+    })
+    it('should render todos', () => {
+        render(todoList)
+        const todos = screen.getAllByTestId('spyTodo')
+        expect(todos).toHaveLength(3)
+    })
+    it('should handle clickDetail', () => {
+        render(todoList)
+        const todos = screen.getAllByTestId('spyTodo')
+        const todo = todos[0]
+        // eslint-disable-next-line testing-library/no-node-access
+        const title = todo.querySelector('.title')
+        fireEvent.click(title!)
+        expect(mockNavigate).toHaveBeenCalledTimes(1)
+    })
+    it('should handle clickDone', () => {
+        render(todoList)
+        const todos = screen.getAllByTestId('spyTodo')
+        const todo = todos[0]
+        // eslint-disable-next-line testing-library/no-node-access
+        const doneButton = todo.querySelector('.doneButton')
+        fireEvent.click(doneButton!)
+        expect(mockDispatch).toHaveBeenCalled()
+    })
+    it('should handle clickDelete', () => {
+        render(todoList)
+        const todos = screen.getAllByTestId('spyTodo')
+        const todo = todos[0]
+        // eslint-disable-next-line testing-library/no-node-access
+        const deleteButton = todo.querySelector('.deleteButton')
+        fireEvent.click(deleteButton!)
+        expect(mockDispatch).toHaveBeenCalled()
+    })
+})
diff --git a/src/store/slices/todo.test.ts b/src/store/slices/todo.test.ts
new file mode 100644
index 00000000..d2bc5d2b
--- /dev/null
+++ b/src/store/slices/todo.test.ts
@@ -0,0 +1,73 @@
+import { AnyAction, configureStore, EnhancedStore } from '@reduxjs/toolkit';
+import reducer, { deleteTodo, fetchTodo, fetchTodos, postTodo, TodoState, toggleDone } from './todo';
+import { ThunkMiddleware } from 'redux-thunk'
+import exp from 'constants';
+import axios from 'axios';
+
+describe('todo reducer', () => {
+    let store: EnhancedStore<{ todo: TodoState }, AnyAction, [ThunkMiddleware<{ todo: TodoState }, AnyAction, undefined>]>
+    const fakeTodo = {
+        id: 1,
+        title: 'test',
+        content: 'test',
+        done: false
+    }
+
+    beforeAll(() => {
+        store = configureStore(
+            { reducer: { todo: reducer }}
+        )
+    })
+
+    it('should handle initial state', () => {
+        expect(reducer(undefined, { type: 'unknown' })).toEqual({
+            todos: [],
+            selectedTodo: null,
+        })
+    })
+    it('should handle fetchTodos', async () => {
+        axios.get = jest.fn().mockResolvedValue({ data: [fakeTodo] })
+        await store.dispatch(fetchTodos())
+        expect(store.getState().todo.todos).toEqual([fakeTodo])
+    })
+    it('should handle fetchTodo', async () => {
+        axios.get = jest.fn().mockResolvedValue({ data: fakeTodo })
+        await store.dispatch(fetchTodo(1))
+        expect(store.getState().todo.selectedTodo).toEqual(fakeTodo)
+    })
+    it('should handle deleteTodo', async () => {
+        axios.delete = jest.fn().mockResolvedValue({ data: null })
+        await store.dispatch(deleteTodo(1))
+        expect(store.getState().todo.todos).toEqual([])
+    })
+    it('should handle postTodo', async () => {
+        jest.spyOn(axios, 'post').mockResolvedValue({
+            data: fakeTodo,
+        })
+        await store.dispatch(postTodo({ title: 'test', content: 'test' }))
+        expect(store.getState().todo.todos).toEqual([fakeTodo])
+    })
+    it('should handle toggleDone', async () => {
+        jest.spyOn(axios, 'put').mockResolvedValue({ data: fakeTodo })
+        await store.dispatch(toggleDone(fakeTodo.id))
+        expect(store.getState().todo.todos.find((v) => v.id === fakeTodo.id)?.done).toEqual(true)
+    })
+    it('should handle error on postTodo', async () => {
+        const mockConsoleError = jest.fn()
+        console.error = mockConsoleError
+        jest.spyOn(axios, 'post').mockRejectedValue({ response: { data: { title: ['error'] }}})
+        await store.dispatch(postTodo({ title: 'test', content: 'test' }))
+        expect(mockConsoleError).toBeCalled()
+    })
+    it('should handle null on fetchTodo', async () => {
+        axios.get = jest.fn().mockResolvedValue({ data: null })
+        await store.dispatch(fetchTodo(1))
+        expect(store.getState().todo.selectedTodo).toEqual(null)
+    })
+    it('should handle not existing todo toggle', async () => {
+        const beforeState = store.getState().todo
+        jest.spyOn(axios, 'put').mockResolvedValue({ data: { ...fakeTodo, id: 10 }})
+        await store.dispatch(toggleDone(2))
+        expect(store.getState().todo).toEqual(beforeState)
+    })
+})
diff --git a/src/store/slices/todo.ts b/src/store/slices/todo.ts
index 5f1a2dce..8b49fa71 100644
--- a/src/store/slices/todo.ts
+++ b/src/store/slices/todo.ts
@@ -60,11 +60,6 @@ export const todoSlice = createSlice({
   name: "todo",
   initialState,
   reducers: {
-    getAll: (state, action: PayloadAction<{ todos: TodoType[] }>) => {},
-    getTodo: (state, action: PayloadAction<{ targetId: number }>) => {
-      const target = state.todos.find((td) => td.id === action.payload.targetId);
-      state.selectedTodo = target ?? null;
-    },
     toggleDone: (state, action: PayloadAction<{ targetId: number }>) => {
       const todo = state.todos.find((value) => value.id === action.payload.targetId);
       if (todo) {
diff --git a/src/test-utils/mock.ts b/src/test-utils/mock.ts
new file mode 100644
index 00000000..ae612042
--- /dev/null
+++ b/src/test-utils/mock.ts
@@ -0,0 +1,11 @@
+import { PreloadedState } from 'redux';
+import { RootState } from '../store';
+import { configureStore } from '@reduxjs/toolkit';
+import todoReducer from "../store/slices/todo";
+
+export const getMockStore = (preloadedState?: PreloadedState<RootState>) => {
+    return configureStore({
+        reducer: { todo: todoReducer },
+        preloadedState,
+    })
+}