SM2 Encrypt/Sign - Chinese Elliptic Curve Tool Online
100% LocalOnline SM2 public-key tool: generate keypairs, encrypt/decrypt (C1C3C2 per GB/T 32918.4-2016), sign and verify. SM2 is a 256-bit ECC scheme, the Chinese alternative to RSA. Local-only, private keys never leave your device.
TL;DR: SM2 public-key crypto: keypair generation, encrypt/decrypt (C1C3C2), sign/verify — ECC alternative to RSA.
This tool runs entirely in your browser. Open DevTools → Network panel and search your input — it appears in no request.
FAQ
Strength: 256-bit SM2 ECC ≈ 3072-bit RSA with far shorter keys. Performance: SM2 signs faster, RSA verifies faster. Compliance: Chinese standards mandate SM2.
C1C3C2 per GB/T 32918.4-2016 (the newer standard). Legacy systems often use C1C2C3 order — the two are incompatible, so confirm the peer format first.
Uncompressed point: 04 prefix (1 byte) + X (32 bytes) + Y (32 bytes) = 65 bytes = 130 hex chars. The private key is a 32-byte scalar (64 hex chars).
Great for learning, verification, interop debugging and protocol analysis. Production key management (generation, storage, destruction) should use certified crypto modules — this page is for understanding the algorithm.
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