Signal that your domain is for sale directly in its DNS with an RFC 10023 _for-sale record. Set an asking price and a contact, then copy the ready-made TXT record into your DNS host - no marketplace, no listing fee.
An RFC 10023 _for-sale TXT record lets a domain owner signal that a domain is for sale directly in DNS - discoverable by anyone with a lookup, no marketplace needed.
Enter a price and contact in the generator, copy the TXT record it produces (name _for-sale, value v=FORSALE1;...), and add it at your DNS host. It goes live within an hour.