> For the complete documentation index, see [llms.txt](https://docs.ethsign.xyz/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.ethsign.xyz/product-overview/contract-verification.md).
# Contract Verification
### Online EthSign Certified Verification
{% hint style="info" %}
Visit the Digital Signature Verification and Contract Audit tool [here](https://app.ethsign.xyz/verify).
{% endhint %}
Verify the integrity of the contents and cryptographic signatures of any contract signed on EthSign. Note, the contract must be signed by all invited signers to be verified.
Upload the signed PDF to check its contents against the copy of the contract stored on Arweave. View the signers' addresses, creation date, signing dates, document key, and document storage CID.
### Offline EthSign Certified Verification
All documents created and signed on EthSign Signatures are [digitally signed](https://docs.ethers.org/v5/api/signer/#Signer-signMessage) by a private key that EthSign controls and can be [independently verified](https://docs.ethers.org/v5/api/utils/signing-key/#utils-verifyMessage) offline.
**EthSign Certified Signing Address:** `0x0xCB9a3AA2eBa735f4d09Ad5b710989646aBE66e12`
***
To review EthSign's data encryption methods, and learn about upcoming encryption options, see [Signature Verification](/a-deeper-dive/technical-details/signature-verification.md).
---
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