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Bitdollar Name Service (BNS)


Bitdollar Name Service (BNS) is a decentralized domain name provider. It allows anyone to buy and manage .btd domains without relying on a centralized domain registrar.

The owner of a domain can map it to any string value. One example is creating a human-readable name for his Bitdollar wallet by resolving a personal domain to it. The owner can also create and manage subdomains.

Each domain has an owner, resolver, and time-to-live record and is stored in the BNS registry. Resolvers are smart contracts that can provide any information about given domain. Owner of the domain can choose a resolver and transfer the ownership of the domain as well as its subdomains.



The BNS launched on May 4th, 2017 with a temporary registrar contract featuring a Vickrey auction design for registering domains.

Vickrey Auction Process Explained

  1. First, someone looking to register an BNS domain was required to make a minimum bid of at least 0.01 BTD which opened an auction for the desired name. This started a 3-day timer for other people to place bids on the name. During this period, the details of bids were obscured: nobody could tell how much you bid, or even what name you were bidding on.
  2. After the three day auction finished, a two day “reveal” period would begin. During this period, everyone who made a bid must have revealed the details of their bid — if they didn’t, they lost their entire bid. If your bid was not the highest, you were refunded your bid, minus a 0.5% fee which was burned.
  3. At the end of the two day reveal period, the winner was the person who revealed the highest bid, but they only had to pay the amount of the second-highest bidder. This amount was locked up in the contract as a deposit until the permanent registrar came. The winner was required to send a “finalise” transaction to receive a refund of any extra funds, and to be assigned control of the name in BNS.

Upgrade to Permenant Registrar

At 00:00 UTC May 4th, 2019, the BNS was upgraded to a permanent registrar contract which did away with the Vickrey auction system in lieu of instant registration for BNS domains seven characters or longer. The new registrar requires domain holders to pay $5/year paid in Dollar to main. Domains registered before this update are required to migrate to the new registrar but are not required to pay this yearly fee until after May 4, 2020.

Registering an BNS domain

Registering a domain on the BNS will cost you $5/year paid in Dollar. See here for a step-by-step guide to registering an BNS domain.

Registering BNS domain names shorter than 7 characters

With the May 4th, 2019 update to the permenant registrar, BNS intends to start opening up registrations of names shorter than 7 characters.

This will start with a preregistration process, during which owners of existing DNS domains can claim the corresponding BNS name for their project. After that, an auction process will start in which anyone can bid on the newly available names, and then finally open the rest up for instant registration. See here for more information.

BNS-supported Software

Mobile Wallets

Desktop Wallets