Algorand case study
Randomness Oracle
Core Technologies

Generating a source of trusted and secure randomness is difficult, especially on-chain. Yet having one is necessary for decentralised applications that depend on randomised processes, such as lotteries, random NFT drops, games, etc. Crucially, it is not enough for most on-chain applications to use “random-looking” quantities (such as the block seed) as sources of randomness. Instead, block proposers have partial control over these quantities, making it possible for rogue block proposers to break applications that depend on these sources being unpredictable.
An external randomness oracle service is therefore required in order to post random values into the blockchain in a cryptographically trusted manner. Algorand, one of the most advanced layer one blockchains, required such as randomness service and commissioned Applied Blockchain to build and provide one. Full details of the challenge can be found here.


Applied Blockchain was selected by the Algorand Foundation to design, build, host and operate the very first independent Randomness Oracle for the Algorand blockchain. The cryptographic function implemented in the oracle is referred to as a Verifiable Random Function (VRF), and its authenticity is verified by Algorand smart contracts.


The Algorand Randomness Oracle service developed, hosted and operated by Applied Blockchain was launched in mainnet on 17th November 2022, and is now the official source of randomness on the Algorand blockchain. It can be seen providing random numbers at regular intervals in the Algorand blockchain explorer here, and these random values are available to be used by any smart contract deployed on the Algorand blockchain, including in games, generative NFTs, lotteries etc. A guide to using the Randomness Oracle can be found here.

Client Testimonials
Tal Rabin
Head of Research, Algorand Foundation
We are grateful to Applied Blockchain for implementing and maintaining the backend service.
Ori Shem-Tov
Algorand Foundation
It was impressive how competent and professional the [Applied Blockchain] team members were, as well as how well we communicated. We had a great experience working with them, since they always understood the importance of the project, and shared our views. Also whenever we requested a change or fix, we usually got quick responses and solutions, so all in all, the experience was excellent.
logo ori-shem-tov
Ori Shem-Tov
Algorand Foundation