# Install cidrmerge with Homebrew

CIDR merging with network exclusion. Version 1.5.3 via Homebrew; verified from local package data.

## Install

```sh
sudo av install brew:cidrmerge
```

Additional install commands:

### macOS

- Homebrew (100%):

```sh
brew install cidrmerge
```

  Evidence: local Homebrew formula metadata

## Package facts

- **Package key:** brew:cidrmerge
- **Package manager:** Homebrew
- **Version:** 1.5.3
- **Source summary:** CIDR merging with network exclusion
- **Homepage:** <https://cidrmerge.sourceforge.net/>
- **Generated:** 2026-08-03T19:37:03+00:00

## Executables

- cidrmerge (alias)

## Install behavior

- Bottle: not available

## Freshness

- Page generated: 2026-08-03
- Package-manager version: 1.5.3
## Project history and usage

CIDRMerge is a C command-line tool and library for merging CIDR networks while applying whitelist-based network exclusion.

### Project history

The SourceForge project was created in August 2005 by Daniele Depetrini. The homepage describes a CIDR merge implementation whose output is summarized as small as possible, with an optimization library, a command-line program, and conversion scripts for netmask and CIDR formats.

### Adoption history

The homepage says CIDRMerge has been widely used for blacklist merge and optimization and notes use by big ISPs. SourceForge file history shows releases from 1.1.0 in August 2005 through 1.5.3 in July 2008, and Homebrew still packages 1.5.3.

### How it is used

Users feed CIDR-formatted lines on standard input, optionally pass a whitelist file, and receive merged or whitelist-filtered CIDR output. The homepage calls out blacklist optimization, RBLDNS workflows, ACL or routing-table reduction, and network-complement computation.

### Why package nerds care

CIDRMerge is old-school package-nerd material: a small C utility, CVS-hosted on SourceForge, still useful enough to be bottled by Homebrew years after its last upstream release. It reflects the practical sysadmin lineage of packaging compact network-list tools for spam filtering, firewalling, and route-table maintenance.

### Timeline

- 2005: SourceForge project created.
- 2005: cidrmerge-1.1.0 released.
- 2005: cidrmerge-1.5.0 and 1.5.1 released.
- 2008: cidrmerge-1.5.3 released.
- 2026: Homebrew formula still packages cidrmerge-1.5.3.

### Related projects

- The homepage explicitly mentions RBLDNS and Michael Tokarev's qsort code; related package-manager peers in this batch include cidr and cidr2range.

### Sources

- <https://cidrmerge.sourceforge.net/>
- <https://sourceforge.net/rest/p/cidrmerge>
- <https://sourceforge.net/projects/cidrmerge/rss?path=/>
- <https://sourceforge.net/p/cidrmerge/code/>
- <https://formulae.brew.sh/api/formula/cidrmerge.json>


## Security Notes

broad file, network, media, or database tool signal.

- **Geiger risk:** blue / medium
- broad file, network, media, or database tool signal


## Combined YAML source

View the package source record on GitHub. [combined/cidrmerge.yml](https://github.com/mxcl/pkgdb/blob/main/combined/cidrmerge.yml)


## Sources

- pkg.so package database
- Geiger risk classifier
- curated package history
- pkgdb category and tag curation
- cross-ecosystem install command graph