How It Works

Understanding Professional Blockchain Timestamping with Sunlit Daymark

Sunlit Daymark uses the Bitcoin blockchain to create cryptographic proof that a file existed at a specific point in time. This proof is immutable, independently verifiable, and tamper-proof.

Core Concepts

1. Cryptographic Hashing

Every file has a unique "fingerprint" called a hash. Even the smallest change to the file creates a completely different hash. We use SHA-256, the same algorithm that secures Bitcoin.

                    Example:

                    File: "Hello World"

                    Hash: a591a6d4...

2. Merkle Trees

Multiple file hashes are combined into a tree structure called a Merkle tree. Hashes are paired and hashed together repeatedly until we get a single Merkle root - one hash representing all files.

                    Structure:

                    Root → Branches → Leaves

                    (1 hash represents 1000s of files)

3. Bitcoin Blocks

The Merkle root is anchored (embedded) into a Bitcoin block. Bitcoin blocks are created approximately every 10 minutes and are immutable - they cannot be changed once added to the blockchain.

                    Immutability:

                    Block #750000

                    Time: 2024-05-15 14:23 UTC

What Makes Sunlit Daymark Special

Professional Service, Not Just Technical Proof

While other services just give you a technical proof file, Sunlit Daymark provides a complete professional documentation package designed for real-world use.

Flexible Usage

Upload anonymously or create an account to track all your timestamps in one dashboard.

Precise Timing

We record the exact moment you submitted your file hash, plus blockchain confirmations.

Smart Notifications

Email alerts with direct links to your certificate, cover sheet, and online proof.

Professional Documentation

Complete PDF certificates and cover sheets ready for legal or business use.

How It Proves Your File Existed

Your File
document.pdf

SHA-256 Hash
a591a6d40bf420404a011733cfb7b190d62c65bf0bcda32b57b277d9ad9f146e

Merkle Tree
Your hash + other hashes → Merkle root

Bitcoin Block
Merkle root anchored in block #750000

PROOF OF EXISTENCE
Your file existed at 2024-05-15 14:23 UTC

The Timestamping Process

You Upload a File

When you upload a file to Sunlit Daymark, we immediately calculate its SHA-256 hash. We never store your original file - only the hash is used for timestamping.

Privacy First

Your file contents remain private. The hash is a one-way function - it's mathematically impossible to reverse the hash back to the original file.

Hash Submitted to Timestamp Servers

Your file's hash is sent to multiple blockchain timestamp servers for redundancy and security. Each server returns a commitment hash acknowledging receipt of your hash and recording the exact submission time.

Multiple Servers Redundancy Security

Why multiple servers? Sunlit Daymark requires confirmations from at least 2 different timestamp servers (configurable) before marking a timestamp as complete. This provides redundancy against single server failures or malicious actors.

Merkle Tree Construction

The timestamp servers collect hashes from many users over a period of time. These hashes are organized into a Merkle tree structure:

                    Root Hash (Merkle Root)
                    /                    \
        Branch Hash 1          Branch Hash 2
           /        \              /        \
    Leaf 1  Leaf 2      Leaf 3  Leaf 4
      |         |            |         |
   Your    User     User     User
   File    File     File     File

Key insight: The Merkle root (single hash) cryptographically represents ALL files in the tree. If any file hash changes, the entire root changes. This allows thousands of timestamps to be proven with a single hash in the Bitcoin blockchain.

Bitcoin Block Anchoring

The timestamp servers embed the Merkle root into a Bitcoin transaction. This transaction gets included in a Bitcoin block, typically within 1-2 hours.

When a Bitcoin block is mined:

Block height is recorded (e.g., block #750000)
Timestamp is recorded (e.g., 2024-05-15 14:23:45 UTC)
Block hash is calculated (immutable identifier)

Once a block is added to the Bitcoin blockchain, it becomes immutable. Changing any data would require re-mining that block and all subsequent blocks - computationally infeasible with Bitcoin's massive mining power.

You Receive Professional Documentation

What makes Sunlit Daymark special: You get a complete documentation package, not just a basic proof file.

Professional PDF Certificate

Complete cryptographic proof chain
Step-by-step verification instructions
Human-readable proof document
Perfect for legal and professional use

PDF Cover Sheet

Attach to printed documents
Include with original files
Professional filing documentation
Clear timestamp summary

Technical Proof File (.ots)

Cryptographic proof (<1KB)
Merkle tree path to root
Bitcoin block information
Server attestations

Email Notification

Automatic completion alert
Direct links to all documents
Online certificate access
Convenient download links

Sunlit Daymark Advantage

We record the exact time your file hash was submitted to our service, plus the blockchain attestations - giving you complete proof of when your file existed and when you claimed it.

How Verification Works

Independent Verification

Anyone can verify your timestamp without trusting Sunlit Daymark. The verification process is:

Hash the file: Calculate SHA-256 hash of the original file
Follow the Merkle path: Use the .ots proof file to trace from your file's hash up through the Merkle tree to the root
Check Bitcoin blockchain: Verify the Merkle root appears in the specified Bitcoin block at the claimed time
Confirm attestations: Verify signatures from multiple timestamp servers

Trust Through Mathematics, Not Authority

You don't need to trust Sunlit Daymark, the timestamp servers, or any third party. The proof is verified against the public Bitcoin blockchain, which is maintained by thousands of independent miners worldwide.

Why This Is Secure & Trustworthy

Immutability

Once data is written to the Bitcoin blockchain, it cannot be changed. Bitcoin's proof-of-work consensus and massive global hash rate make rewriting history computationally impossible.

Transparency

The Bitcoin blockchain is public. Anyone can inspect any block and verify the data. There are no hidden transactions or secret modifications.

Decentralization

Bitcoin is maintained by thousands of independent nodes and miners worldwide. No single entity controls the blockchain, making it censorship-resistant and reliable.

Redundancy

Sunlit Daymark uses multiple timestamp servers and requires confirmations from at least 2 servers. This provides protection against single points of failure.

Real-World Applications

Legal Documents

Prove when contracts, agreements, or legal filings were created. Useful for intellectual property claims, prior art, and compliance.

Research & Development

Timestamp research papers, source code, designs, or inventions to establish priority and protect intellectual property rights.

Digital Media

Prove authenticity and creation time for photos, videos, or artwork. Useful for journalists, photographers, and artists.

Compliance & Auditing

Create tamper-proof audit trails for financial records, compliance documents, or regulatory filings.

Data Integrity

Verify that backup files, database snapshots, or archived data haven't been modified since creation.

Notarization

Create cryptographic proof of document existence without revealing document contents - perfect for confidential materials.

Ready to Get Started?

Create your first blockchain timestamp in seconds. No account required.

Upload Files or Verify Timestamp

Frequently Asked Questions

1-2 hours typically. Your file is timestamped immediately with a pending status. It takes 1-2 hours for timestamp servers to aggregate hashes and submit them to the Bitcoin blockchain. Once included in a Bitcoin block, your timestamp is complete and you'll receive an email with all your documentation.

No. Only the hash (fingerprint) of your file is timestamped. The Bitcoin blockchain contains the Merkle root, which represents thousands of file hashes combined into one. Your original file never leaves your computer during verification, and we don't store file contents.

Your proof still works! The .ots proof file and your original file are all you need. You can verify timestamps using any blockchain timestamping tool, command-line clients, or by manually checking the Bitcoin blockchain. The proof is independent of Sunlit Daymark.

Sunlit Daymark is completely free thanks to efficient blockchain timestamping. There are no blockchain fees because thousands of timestamps are aggregated into a single Bitcoin transaction via Merkle trees. You get professional documentation at no cost.

No. The timestamp is tied to a specific Bitcoin block with a specific timestamp. Bitcoin blocks cannot be backdated or modified once mined. The proof file contains a cryptographic path from your file's hash to the Bitcoin blockchain, which can be independently verified by anyone.

Preliminary: Contains calendar server commitments (proof of submission) but not yet Bitcoin attestations. Larger file size.

Verified: Contains Bitcoin blockchain attestations (proof of inclusion in a block). Pruned and optimized - smaller file size. This is the final, complete proof.

Have more questions?

Start Timestamping Your Files