Frequently Asked Questions
What is Proof of Date?
Proving you have something through a lawyer is expensive – and still relies on trust. We use a better, simpler, and much more affordable solution that’s impossible to dispute or lose.
We take the digital file of whatever it is you want to prove, generate a unique cryptographic signature of it and store it as a token on the world’s most decentralized blockchain. Once recorded, it’s permanently locked, tamper-proof, and verifiable forever.
How can I trust your Proofs are as good as you claim?
Our proofs are considered indisputable and legally reliable. It’s the digital equivalent of sealing an envelope with a tamper-proof stamp: the stamp proves the contents existed at a certain time and haven’t been changed.
When you create a digital file – like a photo, document, or contract – it can be proven that it existed at a specific point in time using a process called hashing.
A hash is like a digital fingerprint for a file. Using a standard method (SHA-256), the file is converted into a long string of numbers and letters that is unique to that exact version of the file. If even one character, or pixel in the file changes, the hash will change completely.
By storing the hash, you don’t need to share the file itself – just its fingerprint. Later, anyone can run the same process on the original file and instantly confirm whether its fingerprint matches the one stored earlier. If it matches, it’s undeniable proof that the file existed at the time the hash was created and has not been altered since.
Are your Proofs suitable for use as legal evidence?
Yes. A SHA-256 hash is widely recognized as a reliable way to prove the existence and integrity of digital files. Courts and legal systems accept this type of cryptographic proof because:
It’s objective and tamper-proof: The hash is generated by a standardized mathematical process. No one can alter the file without changing the hash.
It’s verifiable by anyone: Anyone – judge, lawyer, or independent expert – can run the same process on the file and instantly see if the fingerprint matches.
No trust required: The proof doesn’t require belief in a person’s word or a company’s reputation; it relies on well-established cryptographic standards used around the world.
Because of these qualities, SHA-256 hashes are accepted as reliable digital evidence. They demonstrate that a file existed at a certain time and has not been changed since, making them suitable to support legal cases, contracts, and intellectual property claims.
Our proofs are built on industry-standard cryptography and are widely recognized as reliable digital evidence. While acceptance can depend on the rules of a specific court or jurisdiction, SHA-256 hashing is an internationally trusted method. For important legal matters, we recommend consulting a qualified professional to understand how best to present this type of proof.
How does recording the proof on the blockchain establish when it was created?
When the SHA-256 hash of your file or text is stored in a token on the Cardano blockchain, it becomes part of a permanent and independently verifiable public record. Each blockchain transaction is automatically assigned a timestamp when it is confirmed and added to the blockchain ledger.
The blockchain functions as a neutral third-party timekeeper. It is decentralized, meaning it is maintained by thousands of independent participants worldwide, not controlled by any single person, company, or government. Once recorded, your proof cannot be altered, backdated, or deleted – its timestamp is locked into history.
This makes the blockchain a trustworthy source to demonstrate:
When your proof was created.
That it has remained unchanged since.
In practice, this gives your digital proof a legally persuasive foundation: the blockchain itself serves as an impartial witness to the exact date and time your file’s fingerprint was recorded.
Can I delete a Proof Token after its been created?
No. It is impossible, no one can ever alter or delete the blockchain transaction that contains the digital proof once it’s confirmed.
You can however chose to keep the file or text you used to create your digital proof private and only reveal it if you choose to.
How can you create a Proof of my file without it being sent to you?
The cryptographic hash of your file is created directly in your web browser, on your own device. Your file never leaves your computer – the browser simply reads it locally, generates a one-way digital fingerprint (the hash), and only that small hash value is sent to us. Because a hash cannot be reversed back into the original file, this process ensures your data remains private while still giving you verifiable proof on the blockchain.
How is it possible the same cryptographic hash can't be generated if a file is changed?
A cryptographic hash works like a super-sensitive digital fingerprint. The SHA-256 algorithm looks at every single bit of your file and produces a unique string of numbers and letters. If even the tiniest detail of the file changes – a single character in a document, or one pixel in an image – the resulting hash will be completely different. Because of the way the math behind SHA-256 works, it’s practically impossible for two different files to ever produce the same hash. This sensitivity is what makes hashing so reliable as proof that a file has not been altered.
The digital Proof doesn’t look long enough to be impossible to recreate - is it really secure?
Yes. Even though a SHA-256 hash looks like a string of only 64 characters, it actually represents an astronomically large number – 2²⁵⁶ possible combinations. To put that in perspective, that’s more than the number of atoms in the observable universe. Because of this, the chance of someone deliberately or accidentally creating the same hash from a different file is effectively zero.
In other words, while the proof may look short to the human eye, mathematically it’s impossibly vast, which is why SHA-256 is trusted worldwide for digital security and legal evidence.
Can I verify my Proof Token myself?
Yes. You can easily verify we’ve done what we claim as soon as the proof is created. You can do this by:
Use any SHA256 hash generator on your file to generate its SHA256 cryptographic hash value.
Use the link to the proof token we create for you to view it using any Cardano token viewer. In its metadata section, stored within it on the blockchain, you can see the SHA256 hash value and can confirm it matches the value you just generated yourself.
What blockchain do you create the Proof Token on?
We use Cardano, the world’s most decentralized blockchain. It has the highest Nakamoto Coefficient of any blockchain, meaning control is spread across more independent participants than anywhere else. Cardano has a flawless security record and is maintained by a large global community that collectively runs the network, ensuring it will remain available indefinitely.
For an application like this – where decentralization, security, and long-term reliability are critical – Cardano was the clear choice.
Can I have the Proof Token sent to my own wallet?
Yes of course, but there’s no need to. The Proof token we create exists on the blockchain providing its proof regardless of which wallet holds it. The blockchain transaction that creates it exists on the blockchain forever and can never be altered or destroyed. It is that original transaction which provides the proof that the file or text used to create it is still exactly the same and hasn’t been altered in any way in the future. Viewing the proof token at any point in the future, regardless of which wallet holds it, will always refer back to the blockchain transaction that created it.
If you’d like to have the proof token we create sent to your own wallet and you’re new to Blockchain or Cardano then these are good choices for newcomers:
