Metadata: size property

Non-standard: This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.

Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The read-only size property of the Metadata interface specifies the size, in bytes, of the referenced file or other file system object on disk.


A number indicating the size of the file in bytes.


This example checks the size of a log file and removes it if it's larger than a megabyte.

  (fileEntry) => {
    fileEntry.getMetadata((metadata) => {
      if (metadata.size > 1048576) {
        fileEntry.remove(() => {
          /* log file removed; do something clever here */


This feature has been removed from all specification and is not in the process of being standardized.

Browser compatibility

BCD tables only load in the browser

See also