RFC 10023 Ecosystem & Adoption
RFC 10023 is a recent mechanism for publishing a domain’s availability for sale directly within the DNS. Nevertheless, registries, domain tools, scanners, developer services, and other applications already support the _for-sale record. This page transparently documents the evolution of the ecosystem based on verified sources.
RFC 10023 Adoption Snapshot
Status: 12 Oct 2026- Native integration / discovery9
- Tools, parsers & scanners13
- Guides & documentation4
RFC 10023 Adoption over time
Independent telemetry networks continuously monitor the DNS deployment of RFC 10023 and _for-sale records. To maintain scientific and methodological rigor, data sources with differing scanning methodologies are always presented separately.
Observation History: Active RFC 10023 Listings
Two independent sources, both fetched daily: ForSaleDNS counts active listings within its 343.8M-domain inventory; Domains Monitor counts all domains with a _for-sale record in its full dataset. Different methods – the values are not directly comparable.
The first 2 measurement days (15 Aug 2026 & 16 Aug 2026) were preliminary partial sweeps with 72.2% and 97.6% inventory coverage (dashed). Since 17 Aug 2026, daily sweep completeness (sweepComplete) has remained continuously at 100.0% (latest: 343,818,996 of 343,818,996 domains). The multi-month baseline audit cycle (baselineComplete) is documented as in progress (false). The calculated change (+27.4%) refers strictly to the observed ForSaleDNS dataset across complete sweeps and does not represent global adoption growth.
The data snapshot refers to the latest measurement published by the source. The last successful fetch indicates when rfc10023.de last retrieved the source successfully.
The series shown originate from different independent scan and discovery systems. Values from different providers are not directly comparable due to differing data sources and scanning methodologies.
Historical ForSaleDNS values are retrieved directly from the documented Adoption History API. Our own Domains Monitor measurements on rfc10023.de are continuously recorded since 24 September 2026.
Longitudinal Zone Scan Recording
Where _for-sale records are published
Baseline study "The State of For-Sale DNS 2026" by ForSaleDNS: 341,642 domains with a valid RFC 10023 signal, analysed by TLD and tag usage.
Top 10 TLDs
- .nl193,999 (56.8 %)
- .de38,174 (11.2 %)
- .uk20,005 (5.9 %)
- .be19,517 (5.7 %)
- .eu18,053 (5.3 %)
- .fr8,306 (2.4 %)
- .se7,440 (2.2 %)
- .com7,125 (2.1 %)
- .ch5,438 (1.6 %)
- .at5,259 (1.5 %)
DACH (.de, .at, .ch): 48,871 domains = 14.3 %. .de ranks second behind the pilot TLD .nl.
Tag usage
- fcod · registry code98.22 %
- furi · contact / listing URI64.07 %
- fval · price25.28 %
- ftxt · free text0.04 %
Three Levels of RFC 10023 Adoption
To prevent marketing exaggeration, we strictly distinguish between real technical execution and mere informational articles.
Automated Ingestion & Processing
A service or marketplace actively and automatically queries the _for-sale TXT record, extracts tags (fval, furi), and surfaces the sale intent directly in search results or checkout flows.
Scanners, APIs, MCP & Parsers
Software, libraries, or developer tools providing scanners, syntax parsers, DoH validators, Model Context Protocol (MCP) servers, or browser extensions for RFC 10023 inspection.
Awareness & Setup Guides
A registrar or DNS provider explains the standard in knowledge bases or tutorial articles and documents how customers can configure the _for-sale record without actively evaluating signals itself.
From DNS Signal to Domain Discovery
RFC 10023 separates the sale signal from proprietary landing pages and closed broker marketplaces. Domain owners publish availability directly in the global DNS hierarchy. Third-party tools and registrars evaluate this signal automatically.
Decides to offer domain for sale
v=FORSALE1;fval=EUR...
Port 53 / DoH / DNSSEC
Automated resolution & parsing
Buyer discovers domain in search
Who Already Supports RFC 10023?
SIDN Labs
Research lab of Dutch registry SIDN and co-author of RFC 10023. Maintains reference portal rfc10023.nl, official documentation, and automated scans in the .nl zone.
INWX
INWX documents in its blog how the _for-sale DNS record can be configured in nameserver management to mark domains for sale.
ForSaleDNS
Specialized search engine and discovery index for domains publishing standard-compliant RFC 10023 _for-sale TXT records.
IPWhois.net
DNS and Whois lookup utility detecting and parsing _for-sale TXT signals in domain lookups.
IPAddress.to
DNS analysis utility detecting and checking active RFC 10023 records with syntax feedback in API output.
Inspect My DNS
Technical DNS diagnostic utility highlighting a visual notice and syntax details when a _for-sale label is detected.
DomainToolBelt
Aftermarket research suite for domain investors supporting DNS-based _for-sale market signals.
Domains Monitor
Monitoring project providing telemetry on active _for-sale DNS records across global domain zones.
DomainKits MCP
Model Context Protocol server (ABTdomain / Lyalpha) with documented RFC 10023 support in the API for AI agents.
For-Sale MCP (CultriX)
Open-source Model Context Protocol server (Cloudflare Worker) enabling LLM agents to query _for-sale records autonomously.
ForSale Browser Extension
Functional Chromium browser extension (author: Marco Davids) checking visited websites for _for-sale DNS signals via DoH.
Atom
Marketplace platform automatically publishing RFC 10023 DNS records (_for-sale TXT) for all eligible listings using Atom nameservers. Includes listing URLs (furi), Buy Now prices (fval), and status notes (ftxt) with automated synchronization and removal upon sale or delisting.
happyDomain
Open-source DNS management platform with native support for RFC 10023 _for-sale records in its configuration editor.
tldx
Open-source CLI tool for bulk domain availability checking via RDAP, DNS, and WHOIS with integrated RFC 10023 for-sale filter.
RDAP.ai
AI-powered domain research platform with RFC 10023 support for detecting DNS-based for-sale signals.
EasyDNScheck
Free DNS checking service detecting and displaying _for-sale TXT records per RFC 10023.
badge.forsale
Dedicated badge service for generating privacy-compliant HTML/CSS badges for RFC 10023 compliant domain sales pages.
for-sale-dns.hx-std.com
Simple and lightweight online tool for generating and validating RFC 10023 _for-sale DNS records.
Dotweekly
Domain news and marketplace platform featuring integrated RFC 10023 generator and WHOIS lookup with _for-sale signal display.
Namegarage
Marketplace publishing an RFC 10023 record in every zone it controls, pointing directly to the respective listing and price.
ELITEDOMAINS
German registrar and marketplace automatically providing _for-sale records for external domains and non-.de TLDs. Not yet possible for .de (DENIC NSENTRY does not allow TXT records).
NameShift
Marketplace publishing RFC 10023 records with listing URL (furi), price (fval) and minimum price (fmin) for listed domains. Listed as supporter on rfc10023.nl; verified via DNS lookup.
Zycon Domains
UK domain seller publishing _for-sale records for its listed domains. Listed as supporter on rfc10023.nl; verified via DNS lookup.
SLD Checker (DNForum)
Free cross-TLD research tool by DNForum (beta) with a dedicated "For-sale signals (RFC 10023)" section for detected sale signals.
DNSAudit.io
DNS security and audit platform that automatically detects _for-sale records, distinguishes malformed records and wildcard answers, and displays content safely (escaped, links not followed).
namecheap-python CLI
Open-source Python SDK and CLI for the Namecheap API whose official CLI documentation explains how to add and remove RFC 10023 _for-sale TXT records from the command line.
RFC 10023 Adoption Timeline
Verified technical milestones since the publication of IETF RFC 10023.
IETF RFC 10023 officially published
The RFC Editor publishes RFC 10023 as an IETF publication (Category: Informational, author: Marco Davids, SIDN Labs), describing an operational convention for _for-sale TXT records.
Domains Monitor launches global tracking
First systematic telemetry of active _for-sale records across gTLDs and ccTLDs.
INWX publishes DNS configuration guide
INWX becomes one of the first European registrars to document how customers can configure the _for-sale TXT record.
Launch of ForSaleDNS search engine
Forsaledns.net launches as a specialized search engine and discovery index for domains signaling sale via RFC 10023.
Model Context Protocol (MCP) integration for AI agents
First MCP servers (DomainKits MCP, RFC-10023-MCP) enable autonomous AI agents to query domain sales signals directly in the DNS.
SIDN Whois shows "for sale" button for .nl domains
The .nl registry SIDN natively evaluates _for-sale records: for .nl domains with an RFC 10023 record, its Whois page automatically shows a green "for sale" button. First evaluation at registry level (example cupz.nl, documented by RFC author Marco Davids).
RFC 10023 added to Website Specification
specification.website — a platform-agnostic, open-source specification of technical website standards — adds _for-sale DNS as a documented feature, referencing RFC 10023 as the formal basis for machine-readable sale signals.
Namegarage publishes _for-sale records across its entire portfolio
Marketplace Namegarage publishes an RFC 10023 record in every zone it controls, pointing directly to the respective listing and price – one of the first marketplaces with a full rollout.
ELITEDOMAINS publishes _for-sale records automatically
German registrar and marketplace ELITEDOMAINS automatically provides RFC 10023 records for external domains and non-.de TLDs. Not yet possible for .de, as DENIC NSENTRY delegations do not allow TXT records.
Launch of rfc10023.de Ecosystem Tracker
rfc10023.de launches the independent Ecosystem & Adoption Tracker documenting verified tools and telemetry.
Atom begins platform-wide RFC 10023 rollout
Atom announces automated deployment of RFC 10023 records for all listings hosted on Atom nameservers, providing machine-readable listing URLs, Buy Now pricing, and status notes synchronized with marketplace inventory.
Unusual increase in the Domains Monitor dataset
+87,633 detected domains versus the previous observation. The cause has not been conclusively established.
RFC 10023 Developer & Validator Tools
We provide open reference utilities for generating, inspecting, and testing _for-sale records. In accordance with strict neutrality rules, our own tools are categorized separately from third-party ecosystem integrations.
Inspect _for-sale TXT records live via DNS-over-HTTPS with DNSSEC validation.
Generate standard-compliant multi-record RRsets for Cloudflare, Hetzner, INWX, and BIND.
Audit up to 50 domains simultaneously for RFC 10023 signals with rate limiting.
Free public JSON endpoint for automated validation scripts and developer bots.
Step-by-step guides for DNS setup across Hetzner, Cloudflare, Netcup, and INWX.
100% privacy-compliant HTML/CSS badges for domain sales landing pages.
Methodology & Data Governance
This directory is based exclusively on publicly verifiable information. An entry does not automatically imply a full native RFC 10023 integration; we rigorously distinguish between native automated processing, developer tools/scanners, and pure documentation.
Published telemetry figures originate from independent third-party monitoring projects. Different scanners apply distinct data sources, discovery zones, and measurement methodologies, meaning figures cannot be directly cross-compared. Exact calendar dates are only published when backed by definitive source records; otherwise, month-level resolution is applied.
Historical adoption telemetry is recorded prospectively on a daily schedule without retroactive estimation or synthetic data interpolation.
Verification policy: Every integration requires a verifiable public source URL. Entries without documented evidence will not be published.
Missing an Implementation or Tool?
Do you operate a scanner, registrar guide, DNS utility, or AI tool that supports RFC 10023? Submit your integration with a verifiable public URL for editorial review.