input formats

Input formats

iprange accepts one entry per line. All formats can coexist in the same file.

IPv4 (default mode)

Addresses and CIDRs

Format	Example	Expansion
Dotted decimal	1.2.3.4	Single IP
CIDR prefix	1.2.3.0/24	1.2.3.0 - 1.2.3.255
Dotted netmask	1.2.3.0/255.255.255.0	Same as /24
Abbreviated	10.1	inet_aton() expansion
Decimal integer	16909060	1.2.3.4
Octal	012.0.0.1	10.0.0.1 (leading zero = octal)
Hex	0x0A000001	10.0.0.1

IPv4 parsing uses inet_aton(), which accepts all the above forms. Be careful with leading zeros — 010.0.0.1 is octal 8.0.0.1, not decimal 10.0.0.1.

By default, CIDRs are normalized to the network address: 1.1.1.17/24 is read as 1.1.1.0/24. Use --dont-fix-network to disable this.

The default prefix for bare IPs (no / suffix) is /32. Change with --default-prefix N.

Ranges

Format	Example	Meaning
IP range	1.2.3.0 - 1.2.3.255	Explicit start-end
CIDR range	1.2.3.0/24 - 1.2.4.0/24	Network of first to broadcast of second
Mixed	1.2.3.0/24 - 1.2.4.0/255.255.255.0	CIDR and netmask can be mixed

The dash can have optional spaces around it.

Hostnames

Hostnames (one per line) are resolved via parallel DNS queries. In IPv4 mode, only A records are resolved. If a hostname resolves to multiple IPs, all are added.

See DNS resolution for threading and configuration.

IPv6 (-6 mode)

Addresses and CIDRs

Format	Example	Notes
Full notation	2001:0db8:0000:0000:0000:0000:0000:0001
Compressed	2001:db8::1	Standard :: compression
Loopback	::1
CIDR	2001:db8::/32	Prefix 0-128
IPv4-mapped	::ffff:10.0.0.1
Plain IPv4	10.0.0.1	Auto-normalized to ::ffff:10.0.0.1

IPv6 parsing uses inet_pton(AF_INET6).

Ranges

IPv6 ranges use the same addr1 - addr2 syntax. Both endpoints must be the same address family — a range like 10.0.0.1 - 2001:db8::1 is rejected as a mixed-family error.

Hostnames

In IPv6 mode, hostnames are resolved for both AAAA and A records. A-record results are normalized to IPv4-mapped IPv6 (::ffff:x.x.x.x).

Comments and whitespace

• # or ; at the start of a line marks it as a comment.
• # or ; after an IP/range/hostname starts an inline comment (rest of line ignored).
• Empty lines and leading/trailing whitespace are silently skipped.

File inputs

Regular files

iprange file1.txt file2.txt file3.txt

Each file argument is loaded as a separate ipset. For modes like --compare, each file appears as a separate column in the output.

stdin

cat blocklist.txt | iprange -
# or just:
cat blocklist.txt | iprange

If no file arguments are given, stdin is assumed. Explicit - reads stdin.

File lists (@filename)

iprange @my-lists.txt

The file my-lists.txt contains one filename per line. Comments (#, ;) and empty lines are ignored. Each listed file is loaded as a separate ipset.

# my-lists.txt
/path/to/blocklist-a.txt
/path/to/blocklist-b.txt
# /path/to/disabled.txt

Feature detection: iprange --has-filelist-loading exits 0 if supported.

Directory loading (@directory)

iprange @/etc/firehol/ipsets/

All regular files in the directory are loaded (sorted alphabetically), each as a separate ipset. Subdirectories are not traversed.

Feature detection: iprange --has-directory-loading exits 0 if supported.

Naming for CSV output

Any file argument can be followed by as NAME to override its name in CSV output:

iprange --compare --header file1.txt as "Blocklist A" file2.txt as "Blocklist B"

Binary input

Binary files (produced by --print-binary) are auto-detected by their header line:

• IPv4 binary: format v1.0
• IPv6 binary: format v2.0

Loading a binary file of the wrong family is an error. In IPv4 mode, an IPv6 binary file is rejected. In IPv6 mode, an IPv4 binary file is rejected.

Binary files are architecture-specific (no endianness conversion). They are intended as a same-machine cache, not a portable interchange format.