JavaScript Document hasUnpartitionedCookieAccess() Method

What You’ll Learn

document.hasUnpartitionedCookieAccess() is an instance method that returns a Promise resolving to whether this document can use third-party, unpartitioned cookies (see MDN Document: hasUnpartitionedCookieAccess()). MDN calls it a new name for hasStorageAccess(). Learn when each name appears, Limited availability caveats, and how to feature-detect safely.

Introduction

Cookie names in APIs can be confusing. “Unpartitioned” means the classic shared cookie jar for a site — not the partitioned storage browsers use to reduce cross-site tracking. This method asks: does this document already have that access?

MDN: hasUnpartitionedCookieAccess() returns a Promise that resolves with a boolean indicating whether the document has access to third-party, unpartitioned cookies. It is part of the Storage Access API, and it is a new name for Document.hasStorageAccess().

Related tutorials: hasStorageAccess(), hasFocus(), hasRedemptionRecord().

Understanding document.hasUnpartitionedCookieAccess()

An instance method on the Document interface from the Storage Access API (MDN). It takes no arguments and returns a Promise<boolean>. Details match hasStorageAccess() (MDN: see that page for more).

• No parameters — call it with empty parentheses (MDN).
• Return value — a Promise that resolves to true or false (MDN).
• Meaning — whether the document has access to third-party, unpartitioned cookies (MDN).
• Relationship — new name for hasStorageAccess() (MDN).
• Next step — if false, you may call requestStorageAccess() (MDN example).
• Exception — InvalidStateError if the Document is not yet active (MDN).

📝 Syntax

General form of Document.hasUnpartitionedCookieAccess (MDN):

hasUnpartitionedCookieAccess()

Parameters

None (MDN).

Return value

A Promise that resolves with a boolean value indicating whether the document has access to third-party cookies — true if it does, and false if not (MDN). See hasStorageAccess() for more details (MDN).

Exceptions

• InvalidStateError — thrown if the current Document is not yet active (MDN).

MDN quick sample

document.hasUnpartitionedCookieAccess().then((hasAccess) => {
  if (hasAccess) {
    // storage access has been granted already.
    console.log("cookie access granted");
  } else {
    // storage access hasn't been granted already;
    // you may want to call requestStorageAccess().
    console.log("cookie access denied");
  }
});

⚖️ hasUnpartitionedCookieAccess vs hasStorageAccess

Examples Gallery

Examples follow MDN Document: hasUnpartitionedCookieAccess() and practical alias / fallback patterns.

document.hasUnpartitionedCookieAccess().then((hasAccess) => {
  if (hasAccess) {
    console.log("cookie access granted");
  } else {
    console.log("cookie access denied");
  }
});

cookie access granted
(or unsupported / denied depending on browser)

async function checkAccess() {
  const hasAccess = await document.hasUnpartitionedCookieAccess();
  return hasAccess ? "granted" : "denied";
}

checkAccess().then(console.log);

granted

async function run() {
  if (typeof document.hasUnpartitionedCookieAccess !== "function") {
    console.log("hasUnpartitionedCookieAccess missing — try hasStorageAccess()");
    return;
  }
  console.log("hasAccess:", await document.hasUnpartitionedCookieAccess());
}

run();

hasAccess: true
(or missing message on unsupported browsers)

async function hasUnpartitionedCookies() {
  const fn =
    typeof document.hasStorageAccess === "function"
      ? document.hasStorageAccess.bind(document)
      : typeof document.hasUnpartitionedCookieAccess === "function"
        ? document.hasUnpartitionedCookieAccess.bind(document)
        : null;

  if (!fn) return { supported: false, hasAccess: null };

  return { supported: true, hasAccess: await fn() };
}

hasUnpartitionedCookies().then(console.log);

{ supported: true, hasAccess: true }

async function compareNames() {
  const newer =
    typeof document.hasUnpartitionedCookieAccess === "function"
      ? await document.hasUnpartitionedCookieAccess()
      : "missing";
  const older =
    typeof document.hasStorageAccess === "function"
      ? await document.hasStorageAccess()
      : "missing";

  return { newer, older, same: newer === older };
}

compareNames().then(console.log);

{ newer: true, older: true, same: true }
(or newer: "missing" where only hasStorageAccess exists)

🚀 Common Use Cases

• Readable Storage Access code — name that says “unpartitioned cookies” explicitly.
• Chromium embeds — call the newer method when it is present.
• Cross-browser widgets — fall back to hasStorageAccess() (Baseline).
• API docs / teaching — show both names so learners recognize either in the wild.
• Request flows — after false, consider requestStorageAccess() (MDN).
• Defensive UX — still handle real cookie failures (see hasStorageAccess MDN notes).

📝 Notes

• MDN: Limited availability (not Baseline).
• Not Deprecated, Experimental, or Non-standard on MDN.
• MDN: new name for hasStorageAccess(); see that page for more details.
• MDN: part of the Storage Access API.
• MDN: InvalidStateError if the Document is not yet active.
• Related: hasStorageAccess(), hasFocus(), importNode().

💡 Best Practices