Signatures
Status: dev — the signing demo is simulated in-browser; no private keys are generated or transmitted.
Digital Signatures
Sign and verify messages using post-quantum signature algorithms.
Interactive Signing Demo
Simulated cryptographic operations# Click “Sign Message” to generate a signature
# Then try “Verify” to check it
# Use “Tamper Message” to see verification fail
Signature Size: Classical vs Post-Quantum
Compare signature sizes across RSA, ECC, and PQC algorithms.
Algorithm Selection Guide
Code Signing
ML-DSA-65
Fast verification, reasonable signature size. Good for software packages and updates.
TLS Certificates
ML-DSA-65 (or hybrid)
Balanced performance for handshakes. Consider signature aggregation for chains.
Root CA / PKI
SLH-DSA-SHA2-256s or ML-DSA-87
Maximum security for long-lived trust anchors. Hash-based for conservative security assumptions.
IoT / Embedded
ML-DSA-44
Smallest lattice signatures. Fast enough for constrained devices.
JWT / API Auth
ML-DSA-65
Fast signing and verification for stateless authentication tokens.
Document Signing
ML-DSA-65 + timestamp
Pair with a trusted timestamp for non-repudiation and long-term validity.
OpenSSL Examples
# Generate ML-DSA-65 keypair (requires OpenSSL 3.5+)
openssl genpkey -algorithm ML-DSA-65 -out mldsa65.key
openssl pkey -in mldsa65.key -pubout -out mldsa65.pub
# Sign a message
echo "Important document content" > document.txt
openssl pkeyutl -sign -inkey mldsa65.key \
-in document.txt -out document.sig
# Verify signature
openssl pkeyutl -verify -inkey mldsa65.pub -pubin \
-in document.txt -sigfile document.sig
# Check signature size
ls -la document.sig
# document.sig 3309 bytes (ML-DSA-65)
RSA and ECDSA signatures will be forgeable by quantum computers running Shor's algorithm. Start transitioning to ML-DSA or SLH-DSA now to ensure long-term signature integrity.