A bit convoluted but you can using peeringdb.com to get the AS number of their networks then look that AS up in bgp.tools.
https://www.peeringdb.com/org/8896
Microsoft have 4 ASN with 8075 being the largest one.https://bgp.tools/as/8075#prefixes
The only problem with this method is you may catch some other orgs who host their IPs with Azure like Avaya (the PBX and handset company)
Look Into BGP
Thank you all for your input’s !
As I’m not familiar enough with BGP, AS etc…
I think I’ll go for the list generated by
https://github.com/lord-alfred/ipranges
https://github.com/sakib-m/IP-Prefix-List
To start with.Then I’ll see if it’s possible to gather those IP ranges without relying on third party services…
but that seem unfeasible without be connect to a Internet Exchange Point (IXP) right ?