关于浏览器中Cookie物理存储及键值数据存储位置的技术问询

Hey there, let's unpack your questions about how cookies are stored and managed—this is a really solid deep dive into the nitty-gritty of browser behavior!

一、Cookie在物理层面的存储方式 #

Cookies are ultimately saved to your device's local file system, but the exact format varies by browser. Most modern browsers rely on SQLite databases for this job—it's a lightweight, file-based database that’s perfect for efficiently managing thousands of tiny, structured cookie entries. A few older or niche browsers might use plain text files, but SQLite has become the standard because it makes querying and organizing cookies much easier.

二、浏览器中Cookie键值对的具体存储位置 #

Let’s get specific with popular browsers—here’s where you’ll find those name=Alex style key-value pairs:

Chrome/Edge (Chromium-based browsers) #

• Windows: C:\Users\[YourUsername]\AppData\Local\Google\Chrome\User Data\Default\Cookies (this is a SQLite database file)
• macOS: ~/Library/Application Support/Google/Chrome/Default/Cookies
• Linux: ~/.config/google-chrome/Default/Cookies

Inside this SQLite file, there’s a table named cookies where each row represents one cookie. Your name=Alex pair lives in two columns:

• The name column holds the key ("name")
• The value column stores the corresponding value ("Alex")

Other columns in this table track critical metadata: the cookie’s domain, expiration date, path, and flags like whether it’s secure or HttpOnly.

Firefox #

• Windows: C:\Users\[YourUsername]\AppData\Roaming\Mozilla\Firefox\Profiles\[ProfileFolder]\cookies.sqlite
• macOS: ~/Library/Application Support/Firefox/Profiles/[ProfileFolder]/cookies.sqlite
• Linux: ~/.mozilla/firefox/[ProfileFolder]/cookies.sqlite

Firefox also uses a SQLite database, with a moz_cookies table that stores key-value pairs in name and value columns, alongside domain, expiry, and other settings.

Safari #

• macOS: ~/Library/Cookies/Cookies.binarycookies (this is a binary file format, not plain SQLite—you’ll need special tools to read it directly)
• iOS: Stored in the app sandbox, which isn’t easily accessible without jailbreaking.

三、Cookie是否会与其他站点共享？ #

Short answer: No, never—unless explicitly configured to do so (and even then, it’s tightly restricted).

Browsers enforce the Same-Origin Policy for cookies, meaning each cookie is tied to a specific domain (and sometimes a path). For example:

• A cookie set by example.com will only be sent to example.com (or its subdomains like blog.example.com, if the cookie’s domain attribute is set to .example.com)
• A cookie from google.com can’t be accessed or sent to facebook.com, and vice versa.

Even if two different sites use the same cookie key (like both having a name cookie), they’re stored as separate entries in the browser’s database, each tagged with their own domain. The browser will never mix them up when sending data to a website.

内容的提问来源于stack exchange，提问作者Jorge