Check phpipam

https://phpipam.net/

From: "Mehmet Akcin" <mehmet@akcin.net>
To: "North American Network Operators' Group" <nanog@nanog.org>
Sent: Thursday, 5 September, 2019 09:35:19
Subject: IPAM recommendations

Looking for IPAM recommendations, preferably open source, API is a plus (almost must, almost..). 40-50K IPs to be managed.

thanks in advance.