IPv6 IPv4 mapped

ipv6-ipv4-mapped · version 1.0.0 · URLs & IP addresses · free, no key needed

Convert between an IPv4 address and its IPv4-mapped IPv6 form (::ffff:0:0/96), in either direction.

Use when you need to: ipv6 ipv4 mapped · ipv4 to mapped ipv6 · extract ipv4 from mapped ipv6.

Supported

• ipv6 ipv4 mapped
• ipv4 to mapped ipv6
• extract ipv4 from mapped ipv6

Not supported

• IPv4-compatible (deprecated, ::a.b.c.d) form
• NAT64 (64:ff9b::/96) embedding

Behavior

• Input is exactly one of ipv4 or address; unknown fields, both, or neither throw.
• ipv4 is a canonical dotted-decimal IPv4 address; the tool returns address, its IPv4-mapped IPv6 form ::ffff:a.b.c.d in RFC 5952 canonical (lowercase hex, e.g. ::ffff:c0a8:101) form.
• address accepts any RFC 4291 textual form; the tool returns ipv4, the embedded IPv4 address, only if address lies in ::ffff:0:0/96 — otherwise it throws "address is not an IPv4-mapped IPv6 address".

Input

• object

Output

• object

Limits

• max address length: 45

Example

Request input:

{
  "ipv4": "192.168.1.1"
}

Response:

{
  "result": {
    "address": "::ffff:c0a8:101"
  }
}

How to call it

MCP

Connect https://computefirst.net/mcp (setup), then call execute with:

{
  "id": "ipv6-ipv4-mapped",
  "version": "1.0.0",
  "input": {
    "ipv4": "192.168.1.1"
  }
}

HTTP (no key)

curl -X POST https://computefirst.net/v1/tools/ipv6-ipv4-mapped/versions/1.0.0/execute \
  -H "Content-Type: application/json" \
  -d '{"ipv4":"192.168.1.1"}'

The machine-readable contract is at /v1/tools/ipv6-ipv4-mapped/versions/1.0.0.

CLI

node cli.mjs run ipv6-ipv4-mapped 1.0.0 --input input.json --base-url https://computefirst.net

Get the client at /clients/cli/.

Related tools

• IPv4 address offset: Add a signed integer offset to an IPv4 address, throwing if the result leaves the IPv4 address space.
• IPv4 CIDR parse: Parse an IPv4 CIDR block into its network, broadcast, netmask, wildcard mask, usable host range and address counts.
• IPv4 format: Format a uint32 integer string or four octets as a canonical dotted-decimal IPv4 address.
• IPv4 mask convert: Convert between an IPv4 prefix length, dotted subnet netmask, and dotted wildcard (host) mask.
• IPv4 parse: Parse a canonical dotted-decimal IPv4 address into octets and a uint32 integer string.
• IPv4 range to cidrs: Convert an arbitrary IPv4 address range into the minimal list of CIDR blocks that exactly covers it.