Get Your DID: Now You Can Pay with KILT and PayPal

KILT Protocol
Published in
7 min readJan 25


The new KILT website introduces a way to get a KILT DID (decentralized identifier) without using cryptocurrency. This allows users to have their DID — a “digital fingerprint” at the core of their decentralized digital identity — anchored on the blockchain where no one else can ever delete it. DIDs also provide access to the full range of KILT’s identity solutions.

In the physical world, identity starts with your face or fingerprint. KILT brings this model of identity to the digital world, with a DID serving as your digital fingerprint. Identity is then built around your DID by adding credentials or digital certificates. On KILT, you can anchor your DID on the blockchain. This means that unlike an identity card (which should not be confused with identity itself — it’s just a credential) no external body can cancel or delete the core of your identity.

Anchoring a DID: Pay with KILT

Anchoring a DID requires data storage on the KILT blockchain database, which is replicated among multiple computers. Unlike Ethereum, KILT incentivizes cleaning up this database rather than letting it grow for eternity. Every time a user stores data on the chain, they have to put down a small deposit, which they receive back automatically when they remove the data. Storing a DID on the KILT chain requires a deposit of roughly 2 KILT Coins. The deposit never leaves the user’s account. It is just locked and not available for transfers, voting or staking.

If the DID is no longer required, the user can remove the data at any time, which automatically unlocks the deposit and makes it available again.

Once users anchor their DID on the chain they can use the full range of KILT identity solutions. Since KILT DIDs meet W3C industry standards, they are also compatible with any applications that also resolve the KILT DID method.

Anchoring a DID: Pay without KILT

Many people are interested in enjoying the benefits of decentralized identity. But some don’t want the friction of buying or holding crypto in order to put their DID on the blockchain.

B.T.E. BOTLabs Trusted Entity GmbH (BTE), a subsidiary of BOTLabs, the initial developer of KILT Protocol, has created two solutions to address these adoption challenges:

  • A Checkout Service that puts the individual user’s signed DID transaction on the KILT blockchain, and allows payment with PayPal.
  • An enterprise solution for buying large numbers of DIDs for their customers or employees and paying once via bank transfer.

In both cases, the user’s DIDs are generated on their own device in their private wallet, and are unique to the user.

These two services utilize a unique feature of KILT: the account that pays the fees and makes the deposit (the service) does not need to be the same as the account that authorized the transactions (the DID owner). This means that the owner of the DID stays in control of their DID while an external account (the service used) can be used to submit the DID operations to the blockchain and lock the deposit on behalf of the user. The user always stays in control of the DID. No one except the user can delete or add to the DID.

Naturally, both solutions are compliant with KILT’s privacy by design. Here’s how they work:

Checkout Service

Individuals who prefer not to pay with KILT can use the Checkout Service provided by KILT partner BTE. This service can be accessed via the KILT website or through KILT’s Sporran wallet. Getting a DID (anchored on chain) using the Checkout Service currently costs a non-refundable service fee of EUR 4,⁰⁰. Users can pay for this service using PayPal, which may also provide options for paying in other fiat currencies.

The process starts by creating an account in Sporran, which automatically generates DID details as part of the setup process. After clicking “Get your DID” in the Sporran wallet and selecting the Checkout Service option, users are directed to sign with their password in Sporran to prepare the transaction. Then users will be directed to the Checkout Service, which processes their transaction and offers them PayPal to pay for the Checkout Service:

The service then puts the transaction on the blockchain, pays the KILT transaction fees as well as the required deposit, and registers the DID on the blockchain on the user’s behalf. When the order has been processed, the Checkout Service website shows the order has been completed:

Users will be able to see their DID in their Sporran under “Manage DID”.

The Checkout Service has no control over a user’s DID at any point. Once the service makes the deposit required by the blockchain, the deposit is locked forever. Only the user can delete the DID. The DID is now stored on the blockchain, and the user can start building their digital identity around it, knowing that no external party can turn it off.

Enterprise Solution

This service is also relevant for enterprises that want to build on their real-word trust reputation to create a business around digital identity. Or need to equip their customers or employees with DIDs for various reasons, without requiring them to acquire KILT Coins. Some enterprises even have policies that prevent them from holding cryptocurrencies.

Working on a larger scale, these enterprises don’t want to go through the payment process for every single DID and would prefer an automated solution. To meet this need BTE developed an enterprise service. Here’s how it works:

  • The service allows an entity (e.g. a company) to pay once in fiat for a large number of DID deposits.
  • The BTE service then acquires the necessary amount of KILT Coins.
  • The company can develop its own wallet for their customers to store their credentials securely using KILT’s open source software, or integrate the Sporran wallet.
  • Employees or users of the company’s service can then download the company’s wallet on their device and generate their DID which is anchored on the blockchain.
  • Following a similar process to the Checkout Service, the BTE enterprise service communicates with the company’s software to register DIDs on the blockchain as requested via an API, up to the number of DIDs paid for in advance.

As in the Checkout Service, neither the BTE enterprise service nor the company have any control over the DIDs; they cannot revoke them or remove them from the KILT blockchain.

The Checkout Service and enterprise solution represent a significant step forward for KILT Protocol. These innovations add convenience and flexibility that will drive adoption of KILT DIDs across new audiences and industries.


Still have questions? Browse the FAQs below.


Q: Where do users get their DID?

A: The DID is generated on your computer when you create your account in your wallet (Sporran for Checkout Service, or the wallet developed by the provider for other services).

Q: Can other people add credentials to my DID?

A: No. You can request credentials and store them in your wallet on your device. You decide, which credentials you accept and who you share them with. If you wish to make some credentials public (e.g. email address, social media handles) you may link them to your DID, but no one else can do that for you.

Q: How do I know that BTE won’t cancel my DID?

A: BTE / the Checkout Service cannot remove the user’s DID from the blockchain. Only the user can delete their DID.

Q: Can the Checkout Service / Enterprise service / Company control my DID?

A: No. Only you have control of your DID. Once it’s registered on the blockchain, no one can delete or turn off the core of your digital identity besides you. However, if you later decide you don’t need your DID, you can choose to delete it forever.

Q: Once I have my DID anchored on the blockchain what can I do with it?

A: There are already several services “built on KILT” that utilize DIDs including Social KYC and DIDsign. More applications are in development and will be available soon; keep an eye on Twitter or the KILT blog for announcement updates.

Q: How much does Checkout Service cost?

A: You currently pay a non-refundable €4 (or Euro equivalent) using PayPal for the Checkout Service. This includes VAT, the transaction fee, a handling fee for the service, and the equivalent of the deposit.

Q: If I pay for my DID using Checkout Service, can I delete my DID later?

A: Yes, you can delete your DID from the KILT blockchain. If you do so, this DID cannot be recreated.

Q: What happens if I delete my on-chain DID. Is it completely removed from the blockchain?

A: No, records are permanent on the blockchain. However, deleting your on-chain DID invalidates it forever.

Q: If I pay for my DID using Checkout Service and later delete my DID, do I get a refund.

A: No, deposits paid by Checkout Service are not refundable. The deposit is locked forever.

Q: How are deposits calculated?

A: The deposit amount is calculated using a formula based on the size of the data stored multiplied by a scaling factor that can be decreased or increased by governance vote., e.g.:

Number of items * 56 * 0.001 KILT (milliKILT) + (item size, bytes) * 50 * 0.000001 KILT (microKILT)

Q: If KILT Coins increase in price, will the price of a DID increase too?

A: KILT is a decentralized protocol governed by the community of KILT holders; a decision to change the price of a DID would be made by the community. Any KILT Coin holder could create a proposal to change the price, and the community would vote.

Q: Who owns the KILT blockchain?

A: KILT is a decentralized blockchain, meaning it is owned and governed by the community of KILT Coin holders. Read more about KILT governance here.



KILT Protocol

KILT is a blockchain identity protocol for issuing self-sovereign, verifiable credentials. KILT is part of the Polkadot ecosystem.