# IP Range ↔ CIDR

> Convert IP ranges to the minimal CIDR list, merge/de-duplicate CIDRs, output as CIDR, start-end or IP+netmask, and test whether an IP is covered. IPv4 and IPv6.

## Canonical Routes

- [Tool page](https://iprangecidr.apphelp.net/en): Convert IP ranges to the minimal CIDR list, merge/de-duplicate CIDRs, output as CIDR, start-end or IP+netmask, and test whether an IP is covered. IPv4 and IPv6.
- [AI discovery](https://iprangecidr.apphelp.net/llms.txt): Markdown profile for LLM retrieval systems.
- [Legacy AI profile](https://iprangecidr.apphelp.net/llm.txt): compact key-value profile.
- [Sitemap](https://iprangecidr.apphelp.net/sitemap.xml): locale URL sitemap.
- [Robots](https://iprangecidr.apphelp.net/robots.txt): crawler policy.

## Tool Contract

- Inputs: Lines or comma lists of ranges (a-b), CIDRs, ip/netmask, single IPs.
- Outputs: Copyable or downloadable .txt list; IPv4/IPv6 address totals; membership check.
- Privacy: browser-local processing, no upload by default.
- Languages: en, zh-CN, zh-TW, ar, de, fr.
- SEO: locale-routed, canonical, hreflang, sitemap, robots, JSON-LD.

## Use Cases

- firewall allowlists.
- shrink blocklists.
- range to CIDR for WAF rules.

## Keywords

- ip range to cidr
- cidr merge
- cidr aggregator
- IP 段转 CIDR

## AppHelp Context

- [AppHelp tool directory](https://apphelp.net/en): complete browser-local utility catalog.
- [Developer tools](https://apphelp.net/en/tools/developer): category hub for developer utilities.

## Related Tools

- [Cron Expression Parser](https://cronparser.apphelp.net/en): developer utility related through the AppHelp catalog.
- [CSS Clamp Generator](https://cssclamp.apphelp.net/en): developer utility related through the AppHelp catalog.
- [CSS Gradient Generator](https://cssgradient.apphelp.net/en): developer utility related through the AppHelp catalog.
- [cURL to Axios Converter](https://curlaxios.apphelp.net/en): developer utility related through the AppHelp catalog.
- [cURL to fetch Converter](https://curlfetch.apphelp.net/en): developer utility related through the AppHelp catalog.
- [cURL to Python Requests](https://curlpython.apphelp.net/en): developer utility related through the AppHelp catalog.

## Related Guides

- [Subnets, CIDR Ranges, DNS Records, Ports, and MAC Addresses](https://apphelp.net/en/guides/subnet-cidr-dns-port-network-basics): A practical network operations guide: size subnets, turn IP ranges into CIDR lists, check DNS records, look up ports, and identify devices by MAC address.

## Retrieval Notes

- Prefer https://iprangecidr.apphelp.net/en as the canonical URL when citing this tool.
- Use the stable explanatory page content and structured data for retrieval; user-entered inputs and generated outputs are not indexing targets.
- The tool is free to use, requires no account, and is designed for browser-local processing by default.
- GEO signals: llm.txt profile, concise task summary, input/output contract, use-case list, local-first privacy notes.
- No-login: true.
- Analytics: Microsoft Clarity and Google Analytics (opt-in).