CryptoTickets, Ethereum ERC721 tickets, are live and tradeable on OpenSea

5 min readJan 3, 2019


Originally posted by Devin Finzer:

IMPORTANT EDIT: After posting this article, we learned that we weren’t the first to issue tickets on the blockchain. The AlphaWallet team sold valid World Cup tickets by working directly with FIFA. You can read more about that very awesome project here.

We’re super excited to announce that we’ll be issuing tickets for the upcoming NFT.NYC conference on the Ethereum blockchain as ERC721 assets, for sale on OpenSea. Each ticket is a unique ERC721 item, which we call a CryptoTicket. CryptoTickets are instantly re-sellable, transferrable, bundle-able, bid-able, and interoperable.

While you can still purchase some tickets using our Eventbrite form, 50 discounted VIP tickets are available only on OpenSea, alongside 50 discounted general admission tickets.

How we built it

Just another tradeable asset

Building the first version of CryptoTickets actually turned out to be really simple. Because OpenSea is built as a generic marketplace for ERC721, we simply followed our own developer tutorial to create a new ERC721 contract and we immediately had a tradeable asset! We added ERC721 metadata to customize the visual look of the ticket on OpenSea, and we layered on a few customizations for the unique ticket functionality.

Simple proof of ownership

Of course, the core functionality of tickets is being able to prove that you actually bought a ticket on the day of the event. We added a simple proof-of-ownership feature on OpenSea that works for every single ERC721 asset.

To prove you’re the current owner of the ticket (or really any ERC721 asset), you simply go to the ticket on your OpenSea account and click a button to sign a message using your Ethereum account. This generates a QR code with a signature from your account.

An event manager scanning the QR code will be taken to a URL that validates A) that the signed message is valid for the user’s address, and B) that the signer of the message actually owns the item in question on-chain. In the case of tickets, the event manager then has the option to mark the ticket as “used” (which could be stored either on-chain or off-chain).

Why it’s cool

Experts in both ticketing and blockchain are rightly bearish that decentralized ticketing will disrupt incumbent platforms any time soon.

As outsiders to the ticketing industry, we share this skepticism. Nevertheless, we think blockchain-based tickets might occupy a niche in the near term. Similar to activity in the early blockchain gaming ecosystem — which is mostly smaller, indie projects — we think there might be interesting smaller-scale use cases for blockchain tickets.

Tickets as collectibles

Because they can be easily displayed in a multitude of environments, tickets to famous events (like NFT.NYC 😉) might serve as collectibles, in the same way that physical ticket stubs are often kept and cherished. In addition to displaying your ticket on your OpenSea, you could display your ticket in any number of emerging digital environments: your home in Decentraland, trophy cases, or even inside games.

Collectibles as tickets

The “proof of ownership” feature described early is simple and generic: it’s really just a way to prove you own an item with a QR code. Using the same mechanism, existing collectibles could be used as tickets to events. Own a CryptoKitty? Now you can attend KittyCon (not a real event, but it should be).

Advanced auction functionality

Open protocols allows tickets to take advantage of auction mechanics that wouldn’t necessarily be built in vertically integrated ticket marketplaces. Because tickets are ERC721-compatible, they immediately take advantage of all of the cryptocommerce functionality we’ve built at OpenSea. Without any extra work on our end, users can immediately:

  • Dutch auction their CryptoTickets
  • Sell bundles of CryptoTickets (perhaps even with a CryptoKitty or two)
  • Sell in any ERC20 token (stable coins, fiat coins, rewards tokens)
  • Accept bids for tickets
  • Trade CryptoTickets for other items (coming soon!)

Shared incentives for secondary sales

Issuing tickets on the blockchain allows event issuers to programatically enforce symbiotic relationships with secondary marketplaces for tickets. For example, as an event issuer, I could work with a suite of secondary marketplaces to ensure that I still benefit from secondary sales of my tickets. While such schemes were certainly possible in the centralized world, they were often cumbersome to implement and difficult to enforce.

Tracing custody, while preserving good UX

Now for perhaps the most controversial argument. Spencer Noon from Doggie Tail Crypto Capital rightly points out an existing tradeoff between UX and ticket custody tracing:

But could we have a world with both good UX and the ability to trace custody? While Crypto UX is certainly far inferior to centralized UX at the moment, Crypto UX might one day be superior. Imagine a system where “logging in” was simply granting access to your sovereign, decentralized identity. A ticket could be instantly available in an account where all of your “other stuff” (collectibles, gaming items, ENS names) lives.

In such an (admittedly far off) world, it may be possible to accurately track custody while preserving smooth UX for users. If you don’t believe that crypto UX could ever be superior, be sure to check out the Universal Login Project.

Get your VIP ticket today!

If you’re interested in attending NFT.NYC, there are 50 VIP tickets on sale on OpenSea, so grab one today. Or if you’re more of a speculator and not interested in attending the event, you can grab one and resell it right there on the OpenSea marketplace!

If you’re running a crypto conference, you might be interested in working with us on our solution. Reach out to us at if you’d like to issue some tickets on the blockchain. And as usual, if you’re interested in staying involved in OpenSea-related news, sign up for our mailing list and join us on our Discord.




Since 2019, NFT.NYC events have hosted thousands of attendees, hundreds of leading speakers and the best NFT projects.