Streamlined Zero-Knowledge Proof Verification
Built for Developers
Kurier is a REST API built by Horizen Labs that makes zero-knowledge proof verification simple, fast, and affordable. Whether you're building a zk-dApp, a verifiable compute layer, or a privacy-preserving application, Kurier handles proof submission and on-chain verification so you don't have to run your own infrastructure.
Proofs are optimistically verified by Kurier and submitted on-chain to zkVerify or the Base network — a decentralized blockchain dedicated to ZK proof verification.
The Kurier API is available on both mainnet and testnet. Read our guide here.
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Why Kurier?
Secure
An immutable foundation for your zk-dApp. Proofs are submitted on-chain via zkVerify, providing a tamper-proof audit trail for every verification.
Fast
Optimistic verification delivers near-instant results, with on-chain finality available for applications requiring full cryptographic guarantees.
Simple
A single REST API endpoint replaces the need to run a zkVerify node, manage crypto payments, or write custom proof-submission logic.
Interoperable
Designed to support multiple zk-proof types on various blockchain networks. See the full list of supported networks.
What is Zero-Knowledge Proof Verification?
A zero-knowledge proof (ZKP) allows one party to prove to another that a computation was performed correctly — without revealing any of the underlying data. ZK proofs are the backbone of private and scalable blockchain applications, enabling trustless verification at scale.
Traditionally, verifying ZK proofs requires running a full node or complex infrastructure. Kurier abstracts all of that into a single, easy-to-integrate REST API.
Supported ZK Proof Types
Kurier supports the widest range of ZK proof systems available via API:
groth16
The most widely-deployed ZK proof system
fflonk
Efficient PLONK-based proof verification
plonky2
Ultra-fast recursive proofs by Polygon Zero
risc0
RISC-V based zkVM proofs
sp1
Succinct’s performant zkVM
ultrahonk
Aztec’s latest proving system
ultraplonk
Aztec’s PLONK variant
proof of SQL
ZK proofs for verifiable database queries
Get Started in Minutes
Sign up and generate your free API key
Submit a proof via the REST API
Track verification status in real time using your jobID
Receive on-chain confirmation once finalized on zkVerify or Base
Who Uses Kurier?
Kurier is designed for:
zk-dApp developers
Building privacy-preserving applications on EVM chains
zkVM teams
Using risc0, sp1, or plonky2 who need simple proof delivery
Protocol developers
Integrating verifiable computation into smart contracts
Researchers and builders
Exploring ZK proof applications on zkVerify
Roadmap
Submit a New Feature Request
Q4'25
Q1'26
Q2'26
