The standard for secure blockchain applications

OpenZeppelin provides tools to write, deploy and operate decentralized applications. We also protect leading organizations by performing security audits on their systems and products.

The world’s leading projects trust OpenZeppelin

The challenges of building decentralized applications


Economies in which software powers real money are exposed to hacks and attacks.

Developer Experience

Lack of proper development and testing tools increases margin of errors exponentially.


It’s difficult to manage and fix problems in decentralized systems once they're deployed.

Your blueprint for decentralized systems

Reduce barriers to entry by securely implementing blockchain-based technologies, using standard developer tools and platforms.

A library of modular, reusable, secure smart contracts for the Ethereum network, written in Solidity.

  • Leverage standard, tested, and community-reviewed contracts.
  • Most popular library in the industry.
  • Learn from best practices adopted by the ecosystem.
  • Reduce your attack surface by reusing audited code.

A suite of tools to help you develop, test, upgrade, and deploy smart contracts.

  • Interactive commands to accelerate local development.
  • Easy bug-fixing and quick iterations via smart contract upgrades.
  • Seamless integration with OpenZeppelin Contracts.
  • Multi-network support.
  • Compatible with Truffle.

“I have a very high opinion of the OpenZeppelin team and their work”

Brendan Eich
Brendan Eich | Founder of Mozilla and Brave, Javascript creator.

In-depth security audits

In an economy where software code powers real money, security is a top priority. We specialize in auditing in high-impact decentralized systems.

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Start building

Check out our resources for beginner and experienced smart contracts and blockchain developers.