BYTETOOLS

CIDR to IP Range Converter

Convert CIDR notation like 192.168.1.0/26 into its first and last IP address and total address count. Handles many blocks at once, free and in-browser.

3
Blocks parsed
0
Invalid lines
16,777,281
Total addresses

IP ranges

CIDRFirst addressLast addressAddresses
192.168.1.0/26192.168.1.0192.168.1.6364
10.0.0.0/810.0.0.010.255.255.25516,777,216
203.0.113.5/32203.0.113.5203.0.113.51

What is the CIDR to IP Range Converter?

This CIDR to IP Range converter expands any CIDR block into its start and end addresses and total address count.

  • Expands any /0–/32 CIDR block to its first and last address
  • Batch mode: convert a whole list of blocks in one paste
  • Shows per-block and combined total address counts
  • Flags invalid lines individually with a clear reason
  • Copyable start–end output for firewalls and documentation
  • Runs entirely in your browser — nothing is uploaded

How to use the CIDR to IP Range Converter

  1. 1

    Paste one or more CIDR blocks into the input, one per line.

  2. 2

    Review the table showing each block's first address, last address and size.

  3. 3

    Check the totals row for the combined address count across all blocks.

  4. 4

    Click Copy ranges to export every block as start–end range text.

About the CIDR to IP Range Converter

This CIDR to IP Range converter expands any CIDR block into its start and end addresses and total address count. Paste 10.0.0.0/8 and instantly see it spans 10.0.0.0 to 10.255.255.255 with 16,777,216 addresses — no manual binary math required.

It accepts multiple blocks at once, one per line, which makes it ideal for translating firewall allowlists, cloud security groups or geo-IP feeds into human-readable ranges. Invalid lines are flagged individually with the reason, so one typo never hides the rest of the results.

All conversion is unsigned 32-bit arithmetic performed locally in your browser. Your address lists are never uploaded anywhere, and the converted ranges can be copied out in a single click.

Frequently asked questions

How do I convert CIDR notation to an IP range?

Zero the host bits of the address to get the first address, then set them all to 1 to get the last. For 192.168.1.0/26 the host part is 6 bits, so the range is 192.168.1.0 through 192.168.1.63. This tool does the bit math for every block you paste.

How many IP addresses are in a CIDR block?

A /n block contains 2^(32−n) addresses. So a /24 has 256, a /26 has 64 and a /16 has 65,536. The converter shows the exact count next to each block, plus a combined total when you paste several.

Can I convert multiple CIDR blocks at once?

Yes — paste as many blocks as you like, one per line. Each valid line becomes a row with its first address, last address and size, and any malformed line is reported separately without stopping the others.

What is the difference between the network address and the first usable host?

The first address of a block is its network identifier; hosts normally start one above it. This tool reports the raw first and last addresses of the block. For usable host ranges with network and broadcast excluded, use the Subnet Calculator.

Is my IP list private when I use this tool?

Completely. The expansion is simple integer arithmetic done in your browser tab — no server sees your list, and the tool keeps working even with the network disconnected.

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