Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.

The Lock interface of the Web Locks API provides the name and mode of a lock. This may be a newly requested lock that is received in the callback to LockManager.request(), or a record of an active or queued lock returned by LockManager.query().

Note: This feature is available in Web Workers

Instance properties

Lock.mode Read only

Returns the access mode passed to LockManager.request() when the lock was requested. The mode is either "exclusive" (the default) or "shared".

Lock.name Read only

Returns the name passed to LockManager.request() when the lock was requested.


The following examples show how the mode and name properties are passed in the call to LockManager.request(). LockManager is the object returned by navigator.locks.

navigator.locks.request("net_db_sync", show_lock_properties);
  { mode: "shared" },

function show_lock_properties(lock) {
  console.log(`The lock name is: ${lock.name}`);
  console.log(`The lock mode is: ${lock.mode}`);


Web Locks API
# api-lock

Browser compatibility

BCD tables only load in the browser