ECDSA 签名验证工具
粘贴公钥、消息和签名。验证工具会自动识别曲线、签名格式（DER 或原始 r‖s）和编码，然后在本地检查签名。
100% 本地运行——所有操作都在你的浏览器中完成，不会向任何服务器发送数据
How it works
This free ECDSA signature verifier checks a digital signature against a public key and a message, entirely in your browser — no key, message or signature ever leaves your machine. It accepts public keys as PEM (SPKI), JWK or raw SEC1 points, and signatures in DER (ASN.1) or raw r‖s form, in hex or base64, detecting the format and encoding automatically. The curve — P-256, P-384, P-521 or secp256k1 — is read from the key when possible, or inferred by trying every curve that fits the key length. The message is hashed with SHA-256, SHA-384 or SHA-512 (or treated as a precomputed digest), and the signature is verified with the audited @noble/curves library. It also flags non-canonical high-S signatures that Bitcoin and several other ecosystems reject.