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PostStamper

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Overview

Blockchain-verified timestamps for your social media posts using OpenTimestamps

PostStamper - Blockchain Timestamps for Social Media Create verifiable proof of when you posted content online. PostStamper generates cryptographic timestamps anchored in the Bitcoin blockchain using the OpenTimestamps protocol. How It Works Click the stamp button on any supported post A SHA-256 hash is created locally in your browser The hash is submitted to OpenTimestamps calendar servers Within 2-3 hours, your timestamp is confirmed in a Bitcoin block Download the .ots proof file to verify anytime Privacy by Design Your content never leaves your browser. Only the cryptographic hash is sent to timestamp servers—your actual posts, messages, and conversations stay private. One-click timestamping from any supported page Separate stamp (your content) and witness (others' content) options Downloadable .ots proof files Automatic upgrade from pending to blockchain-confirmed Export all timestamps as ZIP Verify proofs against original content Keyboard shortcuts for quick access Built on Open Standards Uses OpenTimestamps, an open-source protocol. Proof files work with any compatible tool and can be independently verified at opentimestamps.org. No Account Required All data stored locally. No registration, no tracking, no data collection.

Details

  • Version
    1.4.0
  • Updated
    January 11, 2026
  • Size
    63.16KiB
  • Languages
    English
  • Developer
    Website
    Email
    chatzis.ath@hotmail.com
  • Non-trader
    This developer has not identified itself as a trader. For consumers in the European Union, please note that consumer rights do not apply to contracts between you and this developer.

Privacy

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The developer has disclosed that it will not collect or use your data. To learn more, see the developer’s privacy policy.

This developer declares that your data is

  • Not being sold to third parties, outside of the approved use cases
  • Not being used or transferred for purposes that are unrelated to the item's core functionality
  • Not being used or transferred to determine creditworthiness or for lending purposes

Support

For help with questions, suggestions, or problems, visit the developer's support site

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