Why do download managers work faster than the default browser downloaders?

Question

I mean, can't Google Chrome's and Firefox'es implement the same logic as the download manager extensions do?

One might say that the download managers use multi threading which not might be a good experience for browsing rest of the web pages; but even in single threaded downloads, even free download managers are much faster : where as the paid ones like IDM are superfast in any case!

Answer 1

The point is not the number of threads but the number of simultaneous downloads. Ie. similar to torrent clients, some dl managers may split a single file into multiple parts and download them simultaneously.

This will result in significant difference in the total time needed to complete the download when the origin server limits the bandwidth per download request. If different parts of the same file are being downloaded by multiple requests simultaneously, the total download speed multiplies.