Prove Your Work. Protect Your Ideas.
Create legally-valid, tamper-proof timestamps for your files using the Bitcoin blockchain. Establish priority, protect intellectual property, and verify document authenticity.
Perfect for patents & prior art • legal documents • research papers • creative works • compliance records
100% Free Service • Anonymous or tracked • Professional documentation
Why Use Blockchain Timestamping?
Immutable Proof
Bitcoin blockchain makes your timestamp tamper-proof and permanent. No one can backdate or modify it.
Independent Verification
Anyone can verify your proof without trusting us. The Bitcoin blockchain is public and decentralized.
Legal Standing
Cryptographic proof accepted by courts worldwide. Superior to traditional notarization methods.
Trusted by researchers, inventors, lawyers, and creators worldwide
What Makes Sunlit Daymark Special?
Flexible Usage: Upload anonymously or create an account to track all your timestamps in one place.
Professional Documentation: Get comprehensive PDF certificates with full cryptographic proof chains and verification instructions.
Cover Sheets: Receive PDF cover sheets to include with printed documents or alongside original files.
Smart Notifications: Email alerts when timestamps complete, with convenient links to certificates and cover sheets.
Precise Timing: We record the exact time your file hash was submitted, plus blockchain attestations for complete proof.
Service Uptime
99.9%
Last 30 daysBlockchain Security
100%
Tamper-proofAvg. Completion
1-2 hrs
Bitcoin confirmationRecent Activity
47
0 pendingTry It Now - Verify a Sample Timestamp
See how timestamp verification works with this real example from the Bitcoin blockchain
Sample Document:
"Hello, OpenTimestamps!"
SHA256: 03ba204e50d126e4674c005e04d82e84c21366780af1f43bd54a37816b6ab340
Blockchain Proof:
Bitcoin Block #750,000
Timestamp: May 15, 2024 14:23 UTC
This document provably existed at this exact time
Upload any file with its .ots proof to verify timestamp
Powerful Features for Every Use Case
Batch Processing
Upload and timestamp multiple files simultaneously. Perfect for document sets, research datasets, and bulk operations.
Independent Verification
Verify timestamps anywhere, anytime. Works without our service - pure mathematical proof against the blockchain.
Smart Dashboard
Monitor all your timestamps with advanced filtering, search by filename, date ranges, and status tracking.
Professional Documentation
Get comprehensive PDF certificates with proof chains, cover sheets for filing, and CSV exports.
Anonymous or Account-Based
Upload without registration or create an account to track and manage all your timestamps.
Smart Email Alerts
Automatic notifications with direct links to your certificate, cover sheet, and online proof.
Precise Submission Timing
We record the exact moment your file hash was submitted, plus blockchain confirmations.
How It Works - Simple 4-Step Process
Upload Your File
We create a SHA256 hash (cryptographic fingerprint) of your file
Privacy: Your file never leaves your device during verification. We only process the hash.
Submit to Timestamp Servers
Your hash is sent to multiple blockchain timestamp servers for redundancy and security
Security: We require confirmations from at least 2 different servers for maximum reliability.
Bitcoin Blockchain Anchoring
Timestamp servers aggregate thousands of timestamps into the Bitcoin blockchain
Why Bitcoin: Most secure and decentralized blockchain. New blocks every ~10 minutes.
Download Your Proof
Get your .ots proof file - mathematical evidence your file existed at that time
Independence: Your proof works without us. Verify anywhere, anytime, forever.
What You Receive with Sunlit Daymark:
- Cryptographic proof file (.ots format) - Mathematical evidence
- Professional PDF certificate - Complete proof chain with verification instructions
- PDF cover sheet - Perfect for printed documents and filing
- Email notification - With direct links to all documents
- Submission timestamp - Exact time we received your file hash
- Blockchain attestation - Bitcoin network confirmation details
Learn the technical details of how blockchain timestamping creates mathematical proof
Frequently Asked Questions
Supported formats: Any file type (PDF, DOC, JPG, PNG, MP4, ZIP, etc.)
Batch processing: Upload multiple files simultaneously
No file storage: We only process the cryptographic hash - your actual file is never stored on our servers
• Your original files are never stored on our servers
• We only process SHA256 hashes (cryptographic fingerprints)
• Hashes cannot be reversed to reveal file contents
• Only the hash goes to the blockchain, not your file
• For verification, your file never leaves your device
• No registration required for basic timestamping
1-2 hours: Full Bitcoin blockchain confirmation (typical)
Up to 24 hours: Maximum time for completion
The delay comes from Bitcoin's ~10-minute block time and timestamp aggregation processes. You can download your proof as soon as it's complete, and you'll receive an email notification with all your documents.
Best practices: Consult with legal counsel about specific use cases. The timestamp establishes when data existed, but legal interpretation varies by jurisdiction and case type.
Mobile: Works on smartphones and tablets
JavaScript required: For file upload and processing
No plugins needed: Pure web-based service
Offline verification: Download tools available for independent verification
Real-World Use Cases
Intellectual Property
Patent applications, invention disclosures, trade secrets, and prior art documentation. Establish priority dates for your innovations.
Legal Documents
Contracts, agreements, legal briefs, and compliance filings. Prove document existence for legal proceedings and regulatory compliance.
Creative Works
Photos, videos, artwork, music, and written content. Protect your creative works and establish copyright priority dates.
Academic Research
Research papers, datasets, experimental results, and thesis work. Establish priority for scientific discoveries and publications.
Data Integrity
Database backups, audit logs, financial records, and archived data. Prove data hasn't been modified since creation.
Software Development
Source code, software releases, configuration files, and documentation. Prove code state at specific points in time.
Built on Proven Technology
Sunlit Daymark uses Bitcoin blockchain timestamping with professional documentation and user-friendly features. The cryptographic proof is mathematically verifiable and independently auditable.
Ready to Protect Your Work?
Join thousands of researchers, inventors, and creators who use blockchain timestamping to protect their intellectual property and establish legal proof of existence.
Free • Secure • Permanent • No Registration Required