> For the complete documentation index, see [llms.txt](https://contracts.synapseprotocol.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://contracts.synapseprotocol.com/elin/contracts-upgradeable-4.5.0/token.md).

# token

- [ERC20](https://contracts.synapseprotocol.com/elin/contracts-upgradeable-4.5.0/token/erc20.md)
- [IERC20Upgradeable](https://contracts.synapseprotocol.com/elin/contracts-upgradeable-4.5.0/token/erc20/ierc20upgradeable.md)
- [ERC721](https://contracts.synapseprotocol.com/elin/contracts-upgradeable-4.5.0/token/erc721.md)
- [ERC721Upgradeable](https://contracts.synapseprotocol.com/elin/contracts-upgradeable-4.5.0/token/erc721/erc721upgradeable.md)
- [IERC721ReceiverUpgradeable](https://contracts.synapseprotocol.com/elin/contracts-upgradeable-4.5.0/token/erc721/ierc721receiverupgradeable.md)
- [IERC721Upgradeable](https://contracts.synapseprotocol.com/elin/contracts-upgradeable-4.5.0/token/erc721/ierc721upgradeable.md)
- [extensions](https://contracts.synapseprotocol.com/elin/contracts-upgradeable-4.5.0/token/erc721/extensions.md)
- [ERC721EnumerableUpgradeable](https://contracts.synapseprotocol.com/elin/contracts-upgradeable-4.5.0/token/erc721/extensions/erc721enumerableupgradeable.md)
- [IERC721EnumerableUpgradeable](https://contracts.synapseprotocol.com/elin/contracts-upgradeable-4.5.0/token/erc721/extensions/ierc721enumerableupgradeable.md)
- [IERC721MetadataUpgradeable](https://contracts.synapseprotocol.com/elin/contracts-upgradeable-4.5.0/token/erc721/extensions/ierc721metadataupgradeable.md)