Censys and LeakIX are a couple options, both providing search capabilities without registering and a bit more functionality upon free registration:
Censys.io example: https://search.censys.io – ‘ip: [10.1.0.129 to 10.1.0.140]’ or ‘ip: 10.1.0.128/25’
Example IP Range Search on Censys
LeakIX.net example: https://leakix.net “Service” – ip:”10.1.0.128
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