署名エラー解説ツール
検証結果は無効なのに、すべて正しいはずだと確信している場合は、鍵、メッセージ、署名を貼り付けてください。このツールは、検証に成功するまでよくある解釈を順に試し、署名側と検証側でどの前提が食い違っているのかを正確に示します。
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How it works
Almost every "invalid signature" between two correct implementations is not broken cryptography — it is two sides silently assuming different conventions. The explainer builds a small grid of those conventions: candidate curves for your key, DER and raw signature readings (including swapped r/s), your message as literal text or hex/base64-decoded bytes, and the usual digests — SHA-256, SHA-384, SHA-512, legacy SHA-1, Bitcoin-style double SHA-256, plus the case where the message already is a digest. Each combination is actually verified with the audited @noble/curves library, in small batches so the page stays responsive. When one combination verifies, you get the exact mismatch and a code-level fix; when none does, you get an honest list of causes no tool can see from these three inputs. Everything runs inside your browser tab — the key, message and signature never leave your machine.