> 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/a-deeper-dive/technical-details/signature-verification.md).

# Signature Verification

The ability to independently verify the validity of a digital signature is just as important as the act of signing, and this is exactly what EthSign Signatures offers. To verify your downloaded PDF file online, head [here](https://app.ethsign.xyz/verify).

## EthSign Certified

All documents that have completed signing are settled on Arweave. Since our document data structure is public and Arweave is an open network, technically anyone can upload data and have it considered "valid" as long as they conform to our data structure. This is not something we condemn — in fact, our game plan is to build a protocol and we love it when others build on top of our standard.

However, sometimes it is still necessary to distinguish an official implementation from a third-party implementation. This is the idea behind the "**EthSign Certified**" stamp - all documents created and signed on the official EthSign platform 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.

We also attest all [document signing actions](https://scan.sign.global/schema/SPS_blSzPTC9SIL9HS52PZXST) and [completions](https://scan.sign.global/schema/SPS_vpnl9gIq-mqOXlBYQMsqf) on [Sign Protocol](https://sign.global).

* EthSign Certified signing address (attest.ethsign.eth): `0x91f0ff8089A78A135E11123D84c07F9D93883E79`

## Verification Page

Users can verify the integrity of the original contents of their completed and downloaded PDF against the Arweave copy and the digital signatures within said downloaded PDF on our [verification page](https://app.ethsign.xyz/verify).