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PDFタイムスタンプ追加

PDF文書にRFC 3161に準拠したセキュアなタイムスタンプを追加します。作成日時の証明と改ざん防止に。

TSA タイムスタンプの PDF をアップロードする

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このツールについて

Timestamp PDF adds RFC 3161 compliant trusted timestamps to your PDF documents using external Time Stamping Authorities (TSA). It provides legally-binding mathematical proof that a document existed in a specific, unaltered state at a precise instant in time.

Select from global trusted TSA servers such as DigiCert, Sectigo, SSL.com, FreeTSA, or MeSign. No personal signing certificates are required to secure your documents against future tampering.

Supports fully secure local hashing before handshake, guaranteeing absolute document contents remain 100% confidential.

使用方法

  1. Upload PDF Document

    Select the target PDF file you want to timestamp.

  2. Select TSA Server

    Choose a trusted global Time Stamping Authority from the list.

  3. Apply and Timestamp

    Click Timestamp to fetch secure response from TSA and embed the token.

使用例

Intellectual Property

Establish clear priority proof of patents, drafts, and ideas before public release.

Financial Auditing

Provide certified tamper-proof logging of ledger archives and balance reports.

Legal Contracts

Lock legal agreements with a trusted time proof to avoid backdating arguments.

よくある質問

What is a trusted timestamp (RFC 3161)?

An RFC 3161 timestamp is a cryptographically signed token issued by a recognized third-party authority (TSA) that links a document hash to a specific, verified clock source.

Do I need a digital certificate?

No, the cryptographic signature is provided directly by the trusted TSA server, making the process effortless for document owners.

Does the TSA see my document contents?

Never. The tool only sends a secure SHA-256 hash of your document to the TSA server, keeping your actual document completely private.

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Security

  • Client-side processingFiles never leave your device
  • No file uploads100% private & secure

Compliance

GDPR Compliant
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