Concurrent Ajax requests in Chrome

You can get max number of simultaneous connection for each browser by running a test (previously on a service like browserscope but the service is dead now, so you may do it manually)

The results based on your version and configurations.

Here is my network test results using Google Chrome Version 72.0.3626.121 (Official Build) (64-bit):

16. data: URLs = yes
15. Link Prefetch = no
14. Cache Resource Redirects = yes
13. Cache Redirects = yes
12. Cache Expires = yes
11. || CSS + Inline Script = no
10. || CSS = yes
9. Async Scripts = no
8. || Script Iframe = yes
7. || Script Image = yes
6. || Script Stylesheet = yes
5. || Script Script = yes
4. Max Connections = 24
3. Connections per Hostname = 6
2. Check Latency = 251
1. PerfTiming = yes

So it's maximum of 6 connections per hostname and 24 for different hostnames for Chrome 72.

Hope it helps.

This behaviour has not been changed for HTTP/1.1.

You can get more clear picture if you enable the WaterFall. If you see the waterfall, at one point of time only 6 request will get fired(sent to server) and rest all will be in pending mode.

Note, request with status "Pending" appearing in the network tab doesn't mean that the request is sent to the server.

Following is the screenshot from Version 74.0.3726.0