XSigi - Blockchain-secured signatures and encryption made simple.

Hey Product Hunt! 👋 I’m Michael, founder of XSigi.com

Today I’m excited to launch XSigi — Blockchain-Controlled Digital Signatures.

XSigi lets you sign, verify, and protect documents with complete transparency and trust.

Every signature is stored in a tamper-proof blockchain ledger, making it verifiable, auditable, and impossible to alter — even by the signer.

💠 What makes XSigi different:

🧾 Blockchain Ledger: Each signature is recorded in a permanent journal — no edits, only new verified entries.

✍️ Ed25519 Signatures: Fast, lightweight, and cryptographically strong digital signing.

🔒 Secure ZIP Packaging: Bundle signed files into password-protected archives using XChaCha20-Poly1305 encryption.

📘 Key Book System: Manage and verify public keys with full transparency.

🧠 Separate Tool: For sensitive text encryption, XSigi also includes a standalone Kyber ML-KEM-1024 (Post-Quantum) encryption module — designed to protect private messages against future quantum attacks.

🎁 Launch Gift: Use code PRODUCTHUNT for 100% off the private plan until 30 Nov 2025.

XSigi is built for people who value digital trust, proof of authorship, and cryptographic security — from developers and notaries to businesses and creators.

Would love your feedback and support!

🌍 https://xsigi.com

📧 info@xsigi.com

▶️ https://www.youtube.com/@XSigi_com

Let’s make digital signatures truly verifiable — and quantum-ready. 🚀

XSigi supports over 15 languages — Arabic, German, English, Spanish, French, Hindi, Italian, Japanese, Dutch, Portuguese (Brazil), Russian, Swedish, Ukrainian, Simplified Chinese, and Traditional Chinese — both on the website and on our multilingual YouTube channel with instruction videos

This is really such an incredible tool! It didn't even take me 5 minutes to send out a document for signing. You're filling the gap in the market, thanks!