NAT/PAT Table Visualizer

Simulate PAT overload mappings, calculate NAT table capacity, and visualize port exhaustion thresholds.

PAT Entry Simulator

Simulate adding NAT entries to see the translation table grow.

Port Exhaustion Reference
PlatformPAT Port RangePorts per IPMax Translations
Cisco IOS/IOS-XE1024–6553564,51264,512 × outside IPs
Cisco ASA1024–65535 (default)64,512Limited by xlate table memory
Linux iptables/nftables1024–65535 (default)64,512Limited by conntrack table size
Windows Server NAT1025–5000 (legacy) / 1024–6553563,511Registry-tunable
RFC 4787 (BEHAVE)Recommends preserving source portPer-endpoint mapping