Decode CBOR binary (RFC 7049) into readable structures — inspect IoT and WebAuthn payloads. Read COSE keys without a parser library — local decoding, free, no signup.
Content reviewed October 2026 · About Toolzum
Decode MessagePack binary into readable JSON structures. Debug compact payloads without hex dumps — local decoding, free, no signup.
Decode JWT headers and payloads instantly — inspect claims, expiry, and algorithm before trusting a token. Debug auth failures in seconds — local processing, free, no signup.
Decode Base64 data URIs back into viewable and downloadable images. Recover pictures from API payloads — local decoding, unlimited saves.
Decode binary strings back to readable Unicode text with strict validation. Recover messages from bit dumps — local decoding, free, no signup.
Convert between plain text and binary in both directions — encode text into its base-2 representation or decode binary strings back to readable text, byte by byte. Files are converted locally in your browser — nothing is uploaded.
WebAuthn attestation, COSE signatures, and constrained IoT — anywhere JSON is too verbose. Inspect here when standards tooling feels heavy.
Common semantic tags (dates, big numbers) decode to readable forms; unknown tags show raw with tag numbers for manual lookup.
CBOR standardizes extensibility via tags (IETF); MessagePack optimizes simplicity. Decode either here; convert between them via JSON.
No — decoding runs locally in your browser. Payloads never leave your device.
MessagePack Inspector
Decode MessagePack binary into readable JSON structures. Debug compact payloads without hex dumps — local decoding, free, no signup.
Protobuf Decoder
Decode protobuf wire format hex bytes into readable field structure. Shows field numbers, wire types, varints, strings, nested messages, and raw hex.