Privacy and Your Files

Privacy by Architecture

TimeProof is designed so that privacy isn’t a policy choice — it’s an architectural guarantee. Your files physically cannot reach TimeProof’s servers because the system never asks for them.

Here’s what happens when you timestamp a file:

You select a file in your browser
Your browser computes the SHA-256 hash locally (in JavaScript)
Only the hash (64 characters) is sent to the server
The hash is anchored on the Polygon blockchain
Your file stays on your machine, untouched

There is no upload form, no file transfer, no cloud storage. The browser’s file reader and crypto APIs handle everything locally.

What TimeProof Sees

Data	TimeProof Sees?	Why
File contents	Never	Hashed locally, not transmitted
File hash (SHA-256)	Yes	Required for blockchain anchoring
Filename	Yes	User-provided, for dashboard display
File size	Yes	Metadata only
File type / EXIF data	No	Not extracted or stored
Your wallet address	Yes	For authentication
Your email (optional)	Only if provided	For notifications, not required
Your IP address	In server logs	Standard web server logging

Why Hashing Protects You

SHA-256 is a one-way cryptographic function. Given a file, you can compute its hash instantly. But given a hash, you cannot work backward to discover the file — not with any computer, not with any amount of time.

This means:

The hash e3b0c44298fc1c... on the blockchain reveals nothing about whether it represents a legal contract, a photograph, or a song
Even if someone knows the hash is a “document,” they can’t determine its contents
Two files that differ by a single byte produce completely different hashes — there’s no “close match” analysis

Practical Example

Consider you timestamp a confidential contract. The blockchain records:

Hash: a7ffc6f8bf1ed76651c14756a061d662f580ff4de43b49fa82d80a4b80f8434a

An observer on the blockchain sees a 64-character hex string. They cannot determine:

What type of file produced this hash
How large the original file was
Who the parties in the contract are
What language the document is in
Literally anything about the file’s contents

Filename Privacy

Filenames are transmitted to TimeProof for display in your dashboard (so you can identify your timestamps). However:

Filenames are not stored on the blockchain — only the hash is
You can use any filename — rename your file before timestamping if you want additional privacy
Filenames are visible only to you (and your organization members, if applicable)
Filenames appear on your certificates — but you control who sees those

If you’re timestamping sensitive documents and want to minimize metadata, you can rename files to generic names like document-001.pdf before hashing.

Blockchain Transparency

The Polygon blockchain is public. Anyone can see:

That a transaction was submitted by TimeProof’s anchor wallet
The hash or Merkle root that was anchored
When the anchoring occurred (block timestamp)

They cannot see:

Which user requested the timestamp
The filename or file size
The file contents
Whether the hash represents one file or many (Merkle root batches)

The connection between a blockchain transaction and a specific user exists only in TimeProof’s database — it’s not on-chain.

Identity Verification Privacy

If you complete identity verification (for Legal-Grade packages):

Data	Handled By	Stored By TimeProof?
Identity documents (passport, ID)	Stripe Identity	No — processed and stored by Stripe
Verification result (pass/fail)	Stripe → TimeProof	Yes — status only
Verification timestamp	Stripe → TimeProof	Yes
Identity hash (for JWS)	Computed locally	Yes — hashed, not raw data

TimeProof receives a verification status from Stripe — not your actual identity documents. Your passport scan, selfie, and personal details remain with Stripe, governed by Stripe’s privacy policy.

The JWS identity attestation contains a hash of your identity — not the identity itself. Third parties can verify the attestation is genuine without learning your personal details.

Zero-Knowledge Verification

TimeProof’s verification model is designed so that third parties can verify a timestamp without learning anything about the file:

You provide the file to the verifier (if you choose to)
The verifier computes the SHA-256 hash
The verifier checks the hash against the blockchain
Result: The file existed before the blockchain timestamp — verified without TimeProof’s involvement

TimeProof doesn’t participate in verification. The verifier needs only the file and access to the public blockchain.

Cookies and Tracking

Technology	Used?	Purpose
Session cookie	Yes	Authentication (HTTP-only, secure)
Tracking cookies	No	Not used
Analytics	Minimal	Basic usage metrics, no cross-site tracking
Advertising	No	No ads, no ad tracking
Third-party trackers	No	Not embedded

The session cookie is functional — it keeps you signed in. It’s HTTP-only (JavaScript can’t read it) and secure (only sent over HTTPS in production).

Your Privacy Summary

Concern	Answer
Can TimeProof see my files?	No — never transmitted
Can the blockchain reveal my files?	No — hash is one-way
Can TimeProof link me to a blockchain transaction?	Yes — in our database (not on-chain)
Can a blockchain observer identify me?	No — your identity isn’t on-chain
Can I use TimeProof anonymously?	Yes — only a wallet address is required
Is my email required?	No — it’s optional, for notifications
Does TimeProof sell data?	No

Security Architecture — how the system is technically secured
Data Retention Policy — what’s stored and for how long
File Size Limits — how client-side hashing works
What Happens If TimeProof Goes Down? — service continuity