diff --git a/src/shared/types/date/index.ts b/src/shared/types/date/index.ts
new file mode 100644
index 0000000..ee257d2
--- /dev/null
+++ b/src/shared/types/date/index.ts
@@ -0,0 +1,5 @@
+export type YYYY = `${number}${number}${number}${number}`;
+export type MM = `${number}${number}`;
+export type DD = `${number}${number}`;
+
+export type DataDateString = `${DD}/${MM}/${YYYY}`;
diff --git a/src/shared/utils/date/date.spec.ts b/src/shared/utils/date/date.spec.ts
index fb49beb..39f0878 100644
--- a/src/shared/utils/date/date.spec.ts
+++ b/src/shared/utils/date/date.spec.ts
@@ -1,4 +1,9 @@
-import { firstDayOfMonthDate, lastDayOfMonthDate } from './date';
+import {
+  daysCountBetween,
+  firstDayOfMonthDate,
+  getDataDateString,
+  lastDayOfMonthDate,
+} from './date';
 
 describe('Check firstDayOfMonthDate func', () => {
   test('Check middle of month', () => {
@@ -87,3 +92,99 @@ describe('Check lastDayOfMonthDate func', () => {
     expect(lastDayOfMonthDate(date)).toEqual(result);
   });
 });
+
+describe('Check getDataDateString func', () => {
+  test('Check middle of month', () => {
+    const date = new Date(2022, 7, 15);
+    const result = '08/15/2022';
+    expect(getDataDateString(date)).toEqual(result);
+  });
+
+  test('Check end of year', () => {
+    const date = new Date(2024, 11, 31);
+    const result = '12/31/2024';
+    expect(getDataDateString(date)).toEqual(result);
+  });
+
+  test('Check start of year', () => {
+    const date = new Date(2024, 0, 0);
+    const result = '12/31/2023';
+
+    expect(getDataDateString(date)).toEqual(result);
+  });
+
+  test('Check with 0 date', () => {
+    const date = new Date(2023, 12, 0);
+    const result = '12/31/2023';
+    expect(getDataDateString(date)).toEqual(result);
+  });
+
+  test('Check with extra month', () => {
+    const date = new Date(2023, 12, 1);
+    const result = '01/01/2024';
+    expect(getDataDateString(date)).toEqual(result);
+  });
+
+  test('Check with extra date', () => {
+    const date = new Date(2023, 11, 33);
+    const result = '01/02/2024';
+    expect(getDataDateString(date)).toEqual(result);
+  });
+
+  test('Check with extra date and month', () => {
+    const date = new Date(2023, 12, 33);
+    const result = '02/02/2024';
+    expect(getDataDateString(date)).toEqual(result);
+  });
+});
+
+describe('Check daysCountBetween func', () => {
+  test('Check middle of month', () => {
+    const date1 = new Date(2022, 7, 15);
+    const date2 = new Date(2022, 7, 21);
+    const result = 6;
+    expect(daysCountBetween(date1, date2)).toEqual(result);
+  });
+
+  test('Check end of year', () => {
+    const date1 = new Date(2024, 11, 31);
+    const date2 = new Date(2024, 10, 30);
+    const result = 31;
+    expect(daysCountBetween(date1, date2)).toEqual(result);
+  });
+
+  test('Check start of year', () => {
+    const date1 = new Date(2024, 0, 0);
+    const date2 = new Date(2023, 11, 31);
+    const result = 0;
+    expect(daysCountBetween(date1, date2)).toEqual(result);
+  });
+
+  test('Check with 0 date', () => {
+    const date1 = new Date(2023, 12, 0);
+    const date2 = new Date(2023, 12, 21);
+    const result = 21;
+    expect(daysCountBetween(date1, date2)).toEqual(result);
+  });
+
+  test('Check with extra month', () => {
+    const date1 = new Date(2023, 12, 1);
+    const date2 = new Date(2022, 7, 21);
+    const result = 498;
+    expect(daysCountBetween(date1, date2)).toEqual(result);
+  });
+
+  test('Check with extra date', () => {
+    const date1 = new Date(2023, 11, 33);
+    const date2 = new Date(2022, 7, 21);
+    const result = 499;
+    expect(daysCountBetween(date1, date2)).toEqual(result);
+  });
+
+  test('Check with extra date and month', () => {
+    const date1 = new Date(2023, 12, 33);
+    const date2 = new Date(2022, 7, 21);
+    const result = 530;
+    expect(daysCountBetween(date1, date2)).toEqual(result);
+  });
+});
diff --git a/src/shared/utils/date/date.ts b/src/shared/utils/date/date.ts
index 6bcb1c9..1d9c979 100644
--- a/src/shared/utils/date/date.ts
+++ b/src/shared/utils/date/date.ts
@@ -1,3 +1,5 @@
+import type { DataDateString } from 'shared/types/date';
+
 export const firstDayOfMonthDate = (date: Date) => {
   const monthIndex = date.getMonth();
   const year = date.getFullYear();
@@ -11,3 +13,21 @@ export const lastDayOfMonthDate = (date: Date) => {
 
   return new Date(year, monthIndex + 1, 0);
 };
+
+export const getDataDateString = (date: Date): DataDateString => {
+  const locale: Intl.LocalesArgument = 'en-En';
+  const options: Intl.DateTimeFormatOptions = {
+    year: 'numeric',
+    month: '2-digit',
+    day: '2-digit',
+  };
+
+  return new Date(date).toLocaleDateString(locale, options) as DataDateString;
+};
+
+export const daysCountBetween = (date1: Date, date2: Date) => {
+  const ONE_DAY = 1000 * 60 * 60 * 24;
+  const differenceMs = Math.abs(date1.getTime() - date2.getTime());
+
+  return Math.round(differenceMs / ONE_DAY);
+};
diff --git a/src/shared/utils/date/index.ts b/src/shared/utils/date/index.ts
index 560d0e6..498ba93 100644
--- a/src/shared/utils/date/index.ts
+++ b/src/shared/utils/date/index.ts
@@ -1,4 +1,6 @@
 export {
   lastDayOfMonthDate,
   firstDayOfMonthDate,
+  getDataDateString,
+  daysCountBetween,
 } from './date';
diff --git a/src/shared/utils/spec-helpers/date/index.ts b/src/shared/utils/spec-helpers/date/index.ts
new file mode 100644
index 0000000..4953ffe
--- /dev/null
+++ b/src/shared/utils/spec-helpers/date/index.ts
@@ -0,0 +1,18 @@
+// eslint-disable-next-line import/no-extraneous-dependencies
+import { fireEvent } from '@testing-library/react';
+
+import type { DataDateString } from 'shared/types/date';
+
+// todo fix
+// eslint-disable-next-line @stylistic/no-extra-parens
+export const getDateCellByDataDate = (container: HTMLElement, dataDate: DataDateString) => (
+  container.querySelector(`[data-date="${dataDate}"]`)
+);
+
+export const pickCellByDataDate = (...params: Parameters<typeof getDateCellByDataDate>) => {
+  const cellElem = getDateCellByDataDate(...params);
+  if (!cellElem) {
+    throw new Error('first cell not found');
+  }
+  fireEvent.click(cellElem);
+};
diff --git a/src/shared/utils/type/index.ts b/src/shared/utils/type/index.ts
new file mode 100644
index 0000000..a11b59d
--- /dev/null
+++ b/src/shared/utils/type/index.ts
@@ -0,0 +1,5 @@
+// @ts-expect-error
+// eslint-disable-next-line @typescript-eslint/no-unused-vars
+export const exhaustiveCheck = (param: never): never => {
+  throw new Error('should not reach here');
+};