IP Allowlist Generator — Firewall Rule Builder
Generate ready-to-paste IP allowlist and blocklist rules for nginx, Apache, iptables, UFW, and AWS Security Groups. Enter IP addresses or CIDR ranges, select your target platform, and get production-ready firewall config instantly.
How to Use IP Allowlist Generator — Firewall Rule Builder
How to Use the IP Allowlist Rule Generator
Step 1: Select Your Target Platform
Choose the server or firewall technology you want to generate rules for:
- nginx —
allow/denydirectives forserver{}orlocation{}blocks - Apache —
mod_authz_hostRequire ipdirectives for Apache 2.4 - iptables —
iptables -A INPUTrules with optional port and protocol - UFW —
ufw allow/deny fromcommands for Ubuntu/Debian firewall - AWS SG — JSON for
aws ec2 authorize-security-group-ingress(allow) or NACL CLI commands (deny)
Step 2: Choose Rule Type
- Allowlist — only the listed IPs are permitted; all others are blocked (a
deny all/ drop rule is appended automatically where applicable) - Blocklist — the listed IPs are explicitly denied; all other traffic is allowed by default
Step 3: Enter IP Addresses
Paste one IP or CIDR range per line. The tool accepts:
- Single IPv4:
203.0.113.10 - IPv4 CIDR:
192.168.1.0/24 - Single IPv6:
2001:db8::1 - IPv6 CIDR:
2001:db8::/32 - Comments starting with
#are ignored
Invalid entries are highlighted and skipped — valid IPs still produce output.
Step 4: Set Port and Protocol (iptables, UFW, AWS)
For platforms that support port-level filtering, optionally enter:
- Port: a single port (
443), a range (8080-8090), or leave blank for any port - Protocol: TCP, UDP, or All
nginx and Apache access control operates at the HTTP request level, so port/protocol are not applicable there.
Step 5: Copy and Deploy
Click Copy Rules to copy the generated configuration. Paste it into the appropriate location:
| Platform | Where to paste |
|---|---|
| nginx | Inside server{} or location{} block |
| Apache | In httpd.conf, <VirtualHost>, or .htaccess |
| iptables | Run as root in terminal or add to startup script |
| UFW | Run each ufw command as root |
| AWS SG | Use as --ip-permissions argument or save as JSON file |
CIDR Notation Quick Reference
| CIDR | Addresses | Example use |
|---|---|---|
| /32 | 1 (single host) | One specific IP |
| /28 | 16 | Small office block |
| /24 | 256 | Class C subnet |
| /16 | 65,536 | Large corporate range |
| /8 | 16.7 million | Entire ISP or region |
Frequently Asked Questions
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