RFC 10023 is an Informational publication published in July 2026 by the IETF ('The _for-sale Underscored and Globally Scoped DNS Node Name'), authored by Marco Davids (SIDN Labs). It defines a machine-readable convention in the DNS for domain owners to publish availability for sale via _for-sale TXT records.

What is the designated DNS node for RFC 10023?

The standardized DNS node is '_for-sale.[domain]', such as '_for-sale.example.com'. A TXT record is placed there starting mandatory with 'v=FORSALE1;'.

Which registries already support RFC 10023?

The Dutch ccTLD registry SIDN (.nl) natively evaluates RFC 10023 during Whois and domain availability searches. The standard is also supported across various registrars, developer tools, and scanners.

Generator

RFC 10023 Generator

Create standard-compliant DNS TXT records for your domains and export copy-paste configurations for Cloudflare, BIND, Hetzner, INWX, Terraform, and CLI.

RFC 10023 Generator

Generate DNS For-Sale TXT Records

IETF RFC 10023 Compliant

1. Domain Name

DNS Leaf Node: _for-sale.example.comRFC 8552 Underscore

2. Price (fval)Negotiable (OBO)

RFC 10023 Section 2.2.4: Price is indicative and non-binding. Conforms to currency + amount syntax.

3. Contact or Marketplace URI (furi)Recommended schemes: https://, http://, mailto:, tel:

4. Optional Note (ftxt)0 / 239 Bytes

Standard default is empty. Example text is only an illustration and not exported automatically.

5. Optional System Code (fcod)RFC 10023 § 2.2.1: Machine code negotiated between cooperating registrars/brokers.

Recommended TTL:

Max. RDATA length: 23 / 255 octets (RFC 1035 compliant)

Important activation note:

Copying these records only generates the DNS syntax. The record becomes active only after you add it as a TXT record in your registrar's or DNS provider's zone editor.

After saving: verify record for example.com in Validator

; RFC 10023 Zonefile for example.com
; Node name: _for-sale.example.com. | Type: TXT | TTL: 3600
_for-sale.example.com. 3600 IN TXT "v=FORSALE1;fval=USD2500"

1 TXT Record

Verification link: rfc10023.de/en/validator?d=example.com

How to publish the record

1. Open DNS Panel

2. Select Type and Name

Choose TXT as record type and set _for-sale as the host or subdomain name.

3. Verify

Paste the generated text string as value. Within minutes you can verify propagation with our validator.

See which services already evaluate this record in the Ecosystem & Adoption Tracker.Ecosystem Tracker →

Citation Reference for Publications & Media

RFC 10023 Editorial Board (2026). RFC 10023 Record Generator & Multi-Format Exporter. rfc10023.de. Retrieved on September 25, 2026, from https://www.rfc10023.de/generator

Published: October 2026 · IETF Informational RFC