The File Certification page allows you to certify any file or document in any format and size on Waves Blockchain.
This page displays the list of your previous certifications by date, each block in this list displays the following:
Date, Reference, File Hash, Transaction ID (linking to waves explorer), Copy the link icon to share the proof of certification in the verification explorer, link to the Proof of Certification PDF
On the top right you will find a button "CERTIFY NOW", this opens the certification form.
By clicking on the CERTIFY NOW button you will access the certification form allowing you to certify any file or document using your Waves account keypair.
The form includes:
File select: Select or drag and drop the file you want to certify
Reference: By default the name of the file, you may change it, limited to 45 characters. Keep in mind this will be public on the Blockchain.
File hash: The sha256 file hash from the selected file
+ Button: Add more files to certify several at the same time
Store file on IPFS: Check this if you wish to upload the file on IPFS (Interplanetary File System), the file will then be public and available for anyone to download
Transaction Fee: Choose to pay the transaction fee in SIGN or WAVES
Certification Fee: The cost in SIGN token per certification or the amount of your certification credit available (cost is 1 credit per certification)
Confirmation button: Sign and broadcast the transaction
HOW TO CERTIFY
Click on the "Select or Drop a file" area to choose your file, this can be any type of file in any size.
Once selected, the name of the file will automatically be used as a reference as well. You can change the reference, up to 45 characters, keep in mind this will be publicly recorded on the blockchain and shouldn't contain any sensitive information.
The file signature (hash) will be calculated and automatically inserted in the File hash field, this hash is unique and any changes made to the file will totally modify this hash.
If you wish to store the file online, you have the option to use the IPFS option by checking the checkbox.
Files stored with IPFS are public, this is not a private storage, anyone knowing the IPFS file hash can access the file online, don't store private and sensitive information on IPFS.
The "Certification fee" zone will display either the cost per certification in SIGN token or the cost in Certification Credit and the Credit balance associated to your account.
Once everything is ok, click "CERTIFY FILE" to open Waves Signer and sign the transaction with your account.
Verify that all the data is correct, then click confirm.
If everything goes well, you will see the following confirmation popin displaying the transaction id, you can use it to retrieve the certification in the SIGN Explorer or directly in the Waves Explorer (raw data)
After a few seconds, the transaction will appear in the transaction history list.
REVOKE A CERTIFICATION
If you needs to revoke a certification, simply click on the cross on the right and confirm the revoke action. This will cost you 1 sign credit or equivalent in sign tokens: