How to Timestamp Documents on Bitcoin Using Simple Proof

In November 2025, El Salvador's Ministry of Foreign Affairs announced it would begin protecting official government records using Bitcoin blockchain technology. The partner making this possible was Simple Proof, a company that has quietly become the go-to solution for institutions that need mathematical proof their documents haven't been altered.

The underlying concept is elegantly simple: take any digital file, compute its cryptographic fingerprint, and embed that fingerprint in a Bitcoin transaction. Once confirmed, you have immutable proof that your document existed at that specific moment in time, verifiable by anyone with a Bitcoin node and no trust required in any central authority.

Here's how to actually do it.

Understanding What a Bitcoin Timestamp Actually Proves

Before walking through the process, it's worth understanding exactly what you're creating. A Bitcoin timestamp doesn't prove who created a document or whether its contents are true. It proves ordering: that a specific cryptographic hash existed before any subsequent block was mined.

Bitcoin's consensus rules require each block timestamp to exceed the median of the previous eleven blocks, creating a reliable chronological anchor. When you timestamp a document, you're creating proof that this exact file, byte for byte, existed no later than when that Bitcoin block was confirmed.

This matters enormously for intellectual property disputes, regulatory compliance, legal proceedings, and institutional records. With generative AI making digital forgery trivially easy in 2026, proactive data sealing at the moment of creation has become a foundational enterprise requirement rather than an optional security layer.

How the OpenTimestamps Protocol Works

Simple Proof uses OpenTimestamps, a protocol that has been in production for nearly a decade. The technical architecture solves an obvious problem: Bitcoin transactions aren't free, so you can't practically embed a hash for every single document that needs timestamping.

The solution is Merkle tree aggregation. OpenTimestamps collects thousands of document hashes, organizes them into a tree structure where each leaf connects mathematically to a single root hash, and then embeds only that root in a Bitcoin transaction. Your individual proof file (a compact .ots file) contains the "Merkle path" connecting your specific document's hash to that Bitcoin block header.

This makes timestamping efficient and scalable while preserving the key property: anyone can independently verify your proof using open source tools and a Bitcoin node. No trusted third party required.

Step-by-Step Process for Timestamping Documents

Preparing Your Document

Start with the final version of whatever you're timestamping. This could be a contract, research data, a photograph, video footage, or any digital file. The critical point: even a single bit change to the file will produce a completely different hash, which means the timestamp won't verify against a modified version.

For documents that may need updates, consider timestamping each version separately and maintaining a clear version history.

Computing the Hash

Simple Proof handles this automatically, but understanding the underlying step matters. The platform computes a SHA-256 cryptographic hash of your file. This produces a 64-character hexadecimal string that uniquely represents your document's contents.

The same file will always produce the same hash. Different files (even with tiny changes) produce completely different hashes. And critically, you cannot reverse-engineer the original file from its hash.

Submitting to the Blockchain

Once you upload your document or provide its hash, Simple Proof submits it to the OpenTimestamps network. Your hash gets aggregated with others into a Merkle tree, and the root is embedded in a Bitcoin transaction.

Bitcoin blocks are confirmed approximately every ten minutes, so there's a short wait. Some timestamps may take longer depending on when they're submitted relative to the next block.

Receiving Your Proof File

After confirmation, you receive an .ots proof file. This small file contains everything needed to verify your timestamp: the Merkle path connecting your document's hash to the specific Bitcoin block header where it was anchored.

Store this proof file alongside your original document. The two pieces together constitute your complete timestamped record.

Verifying a Timestamp

Verification is where the trustless nature of blockchain timestamping shines. Anyone can verify a timestamp independently using open source OpenTimestamps tools and a Bitcoin node. No need to contact Simple Proof or any other service.

The verification process:

1. Compute the hash of the document in question
2. Use the .ots proof file to trace the Merkle path
3. Confirm that the path leads to a hash embedded in a real Bitcoin block
4. Check the block's timestamp for when this proof was created

If the document has been modified in any way since timestamping, the hash won't match and verification will fail. This is the mechanism that makes tampering detectable.

Rolling Timestamps for Continuous Data

In March 2026, Simple Proof introduced rolling timestamps, which enable continuous timestamping of streaming data as it's being generated. Rather than timestamping a completed file after the fact, cryptographic hashes are submitted to the Bitcoin blockchain through OpenTimestamps every few seconds.

This matters for video footage, sensor data, logs, and any other continuous data streams where you need to prove nothing was altered after the fact. Their demonstration at rtsp.simpleproof.xyz shows live video feeds with rolling timestamps being generated in real time.

Real-World Applications

The technology has moved well beyond proof-of-concept. Screven County, Georgia became the first U.S. county to use Bitcoin blockchain technology to secure election results in November 2024. Guatemala's 2023 elections used the same approach. El Salvador now timestamps official government records across multiple ministries.

Beyond government use, blockchain timestamps provide defensible proof for:

• Intellectual property disputes (proving when you created something)
• Supply chain integrity documentation
• Pharmaceutical compliance under FDA 21 CFR Part 11
• EU AI Act documentation requirements for high-risk AI systems
• German GoBD compliance for business records
• Legal tech applications requiring authenticated evidence

Limitations and Considerations

Timestamping proves existence and timing, not authenticity or truth. A timestamped document could still contain false information; the timestamp only proves that particular version of the document existed at that time.

You also need to preserve both the original file and the .ots proof file. Losing either piece breaks the verification chain. For institutional use, this means integrating timestamp storage into your broader document management and backup systems.

Finally, timestamps depend on Bitcoin's continued operation and security. Given Bitcoin's track record and decentralized architecture, this is generally considered an extremely reliable assumption, but it's worth acknowledging.

Getting Started

For individuals or organizations new to document timestamping, Simple Proof offers a straightforward entry point. The process doesn't require technical expertise or cryptocurrency holdings; you're interacting with a service that handles the blockchain mechanics.

For institutions with more complex needs, including rolling timestamps for continuous data or integration with existing document management systems, Simple Proof provides enterprise-grade solutions that scale while maintaining the same trustless verification properties.

The fundamental value proposition remains constant across use cases: mathematical proof of document existence at a specific moment, anchored to the most secure decentralized ledger in existence, verifiable by anyone without relying on any single authority. In an era where digital forgery has become trivially easy, that proof increasingly matters.