---
title: Parse cookie
tags: browser,string
cover: three-vases
firstSeen: 2018-01-13T14:19:21+02:00
lastUpdated: 2020-10-22T20:24:04+03:00
---

Parses an HTTP Cookie header string, returning an object of all cookie name-value pairs.

- Use `String.prototype.split()` to separate key-value pairs from each other.
- Use `Array.prototype.map()` and `String.prototype.split()` to separate keys from values in each pair.
- Use `Array.prototype.reduce()` and `decodeURIComponent()` to create an object with all key-value pairs.

```js
const parseCookie = str =>
  str
    .split(';')
    .map(v => v.split('='))
    .reduce((acc, v) => {
      acc[decodeURIComponent(v[0].trim())] = decodeURIComponent(v[1].trim());
      return acc;
    }, {});
```

```js
parseCookie('foo=bar; equation=E%3Dmc%5E2');
// { foo: 'bar', equation: 'E=mc^2' }
```