# OpenZeppelin Contracts

OpenZeppelin Contracts is a library for secure smart contract development.

Repository: https://github.com/OpenZeppelin/openzeppelin-contracts
Canonical: https://ross.abutalabs.com/products/openzeppelin-contracts
Homepage: https://openzeppelin.com/contracts
Language: Solidity
License: MIT
License Family: permissive
Topics: ethereum, solidity, evm, security, smart-contracts
Last push: 2026-08-26T19:58:34+00:00
Link (homepage): https://openzeppelin.com/contracts
Link (site_page): https://docs.openzeppelin.com/
Link (site_page): https://www.openzeppelin.com/about-us
Link (site_page): https://www.openzeppelin.com/faqs
Link (site_page): https://www.openzeppelin.com/about

## Health v2 (maintenance only)
Score: 89/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 99, release rhythm 71, longevity 100
- inputs: {"age_days": 3684, "days_push": 7, "days_rel": 35, "gap_med": 99, "n_releases_24m": 8}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 27234, forks 12406 (observed 2026-08-28T04:11:47.569754+00:00)

## What it is
OpenZeppelin Contracts is a library of secure, community-vetted Solidity smart contracts for Ethereum and other EVM blockchains. It provides audited implementations of token standards like ERC20 and ERC721, role-based access control, and reusable components, plus an upgradeable variant for proxy-based contracts.

## Use cases
- create an ERC20 token in solidity
- deploy an NFT contract with ERC721
- add role-based access control to a smart contract
- build upgradeable smart contracts with proxies
- secure a defi protocol with audited contract code
- generate a smart contract boilerplate quickly

## When to choose
- you are developing Solidity contracts for Ethereum or any EVM chain and want battle-tested, audited building blocks
- you need standard token implementations (ERC20, ERC721, ERC1155) or access control patterns
- you want to minimize smart contract security risk with community-reviewed code

## When to avoid
- you are developing for non-EVM chains like Starknet or Sui (separate OpenZeppelin libraries exist)
- you need a full dapp framework or deployment tooling rather than contract code
- you require a non-Solidity language for contract development

## Facets
- artifact type: library
- maturity: stable
- function: security, sdk, developer-tools, plugin-system
- domain: blockchain, fintech, security, developer-tools
- platform: cross-platform
- tags: smart-contracts, erc20, erc721, token-standards, access-control, upgradeable-contracts, defi, web3, cryptocurrency, ethereum, evm, solidity

## Member repositories
- OpenZeppelin/openzeppelin-contracts (main) score 89
- OpenZeppelin/openzeppelin-contracts-upgradeable (mirror) score 90

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:11:47.569754+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T16:54:34.082925+00:00, confidence not recorded.
  - readme: https://github.com/OpenZeppelin/openzeppelin-contracts (fetched 2026-08-28T04:11:47.569754+00:00, sha 669b1a7b493c)
  - homepage: https://openzeppelin.com/contracts (fetched 2026-08-29T07:52:07.787628+00:00, sha 3fc211823a55)
  - site_page: https://docs.openzeppelin.com/ (fetched 2026-08-29T07:52:07.791418+00:00, sha 878c1d01266a)
  - site_page: https://www.openzeppelin.com/about-us (fetched 2026-08-29T07:52:07.796803+00:00, sha 2935d3d9ba8e)
  - site_page: https://www.openzeppelin.com/about (fetched 2026-08-29T07:52:07.801070+00:00, sha 4052c47f4b64)
  - site_page: https://www.openzeppelin.com/faqs (fetched 2026-08-29T07:52:07.799144+00:00, sha bd7fba8e4e3b)
- Data as of 2026-08-30T08:39:29.467469+00:00.