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Compare localStorage, sessionStorage and cookies

#html#storage#browser

Answer

	Size	Lifetime	Sent with requests
`localStorage`	~5–10MB	Until cleared	No
`sessionStorage`	~5MB	Until the tab closes	No
Cookie	~4KB	Per `Expires`/`Max-Age`	Yes (every same-domain request)

Session tokens belong in an HttpOnly + Secure + SameSite cookie so JS can't read them (XSS token theft).
The Storage API is synchronous and string-only → you JSON.stringify yourself, and large writes block the main thread.