JWT decoder / JWT parser / JSON Web Token inspector / Bearer token debugger / OAuth ID-token reader / Auth0 + Cognito + Firebase token inspector. Base64URL-decodes header and payload, parses standard claims (iss, aud, sub, exp, iat, nbf, jti), reports algorithm, key id (kid), token type (typ), TTL, and clock-validity (is_expired / is_not_yet_valid / is_currently_valid_by_clock). Does NOT verify signatures — for inspection only, never trust output for auth decisions.