# nibbstack/erc721

The reference implementation of the ERC-721 non-fungible token standard.

Repository: https://github.com/nibbstack/erc721
Canonical: https://ross.abutalabs.com/products/erc721
Language: Solidity
License: MIT
License Family: permissive
Topics: ethereum, contract, contracts, eth, erc721, token, tokens, standard, implementation, smart-contracts, hacktoberfest, erc-721, non-fungible
Last push: 2022-08-10T08:06:18+00:00

## Health v2 (maintenance only)
Score: 23/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 0, release rhythm 8, longevity 100
- inputs: {"age_days": 3040, "days_push": 1484, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1047, forks 393 (observed 2026-08-28T04:03:22.155052+00:00)

## What it is
The reference implementation of the ERC-721 non-fungible token (NFT) standard written in Solidity for Ethereum, Wanchain, and other EVM-compatible blockchains. It provides audited base, metadata, and enumerable token contracts as a starting point for developers building NFTs.

## Use cases
- deploy an ERC-721 NFT contract on Ethereum
- create non-fungible tokens with metadata and symbol support
- implement enumerable NFT collections with total supply queries
- avoid re-implementing the ERC-721 standard from scratch
- launch NFTs on BSC, Avalanche, or other EVM chains
- learn how the ERC-721 token standard works

## When to choose
- you want an audited, battle-tested ERC-721 reference implementation
- you need a minimal, standards-compliant NFT contract base to extend
- you target Ethereum, Wanchain, or other EVM-compatible chains
- you prefer a simple implementation over a full framework

## When to avoid
- you need payable function support out of the box
- you want a feature-rich token framework with advanced capabilities
- you need ERC-1155 multi-token or fungible token standards
- you require actively maintained code with recent updates

## Facets
- artifact type: library
- maturity: maintenance
- function: sdk, security
- domain: blockchain, developer-tools
- platform: -
- tags: erc721, nft, smart-contracts, solidity, token-standard, hardhat, wanchain, binance-smart-chain, avalanche, cryptocurrency, ethereum, evm

## Member repositories
- nibbstack/erc721 (main) score 23

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:03:22.155052+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 2026-08-30T07:01:08.660673+00:00, confidence not recorded.
  - readme: https://github.com/nibbstack/erc721 (fetched 2026-08-28T04:03:22.155052+00:00, sha 40c67251bb70)
- Data as of 2026-08-30T08:39:29.467469+00:00.