The wrong belief to clear first is that this is a way ofparkinga domain. It is close to the opposite. Parking replaces the site with a sales page, which costs you every visitor the domain still has._for-salesits beside a live site in DNS and says nothing to a browser: the homepage keeps serving, the mail keeps flowing, and the record can be added and removed at will. RFC 10023 makes the point explicitly — the convention is designed to work while the domain is still in active use.
It is also not the same thing as registration data. WHOIS and RDAP answer “is this name registered?”; a registered name may still be purchasable, and an unregistered one may not be worth having. That gap is the whole reason the convention exists, and it is why brokers and automated availability services are the intended audience rather than people.
The signal a domain owner most wants to send is the one there has never been a channel for. If you are willing to sell, the interested buyer has no way to learn that short of a cold email to a WHOIS contact that privacy redaction has probably removed. Enquiries that would have been welcome never arrive, and the ones that do arrive are indistinguishable from spam.
Putting the signal in DNS rather than on the page is what makes it useful to the parties who can act on it. A broker or an availability service checking a name resolves it anyway; one extra lookup tells them what a rendered page could not, because nothing on a working homepage says “the domain under this is negotiable”. It is externally checkable, costs one record, and carries no risk to the site itself — a browser never sees it.
Publish a singleTXTrecord at the_for-saleleaf of the zone you are selling, and only while you mean it.
Rules worth getting right the first time:
Sign the zone withDNSSECif you can. An unsignedTXTrecord asserting your domain is for sale, at a price, with a contact URI, is a comfortable thing for someone else to forge.
This site does not ship a_for-salerecord: specification.website is not for sale.