The read-only property is an integer representing the total amount of work that the underlying process is in the progress of performing. When downloading a resource using HTTP, this only represent the content itself, not headers and other overhead.


value =


Specification Status Comment
The definition of 'ProgressEvent.lengthComputable' in that specification.
Living Standard

Browser compatibility

We're converting our compatibility data into a machine-readable JSON format. This compatibility table still uses the old format, because we haven't yet converted the data it contains. Find out how you can help!

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari
Basic support No support (Yes) 3.5 (1.9.1) No support No support No support
Feature Android Edge Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support No support (Yes) 1.0 (1.9.1) No support No support No support

See also

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Contributors to this page: DomenicDenicola, abbycar, fscholz, kscarfone, teoli
Last updated by: DomenicDenicola,