Internet Assigned Numbers Authority Concise Binary Object Representation (CBOR) Tags Created 2013-09-19 Last Updated 2023-04-26 Available Formats [IMG] XML [IMG] HTML [IMG] Plain text Registry included below • CBOR Tags CBOR Tags Expert(s) Carsten Bormann, Christian Amsüss Reference [RFC8949] Note All registration requests must include the template from [RFC8949]. Available Formats [IMG] CSV Range Registration Procedures 0-23 Standards Action 24-32767 Specification Required 32768-18446744073709551615 First Come First Served Tag Data Item Semantics Reference Template 0 text string Standard date/time string; see Section 3.4.1 [RFC8949] 1 integer or float Epoch-based date/time; see Section 3.4.2 [RFC8949] 2 byte string Positive bignum; see Section 3.4.3 [RFC8949] 3 byte string Negative bignum; see Section 3.4.3 [RFC8949] 4 array Decimal fraction; see Section 3.4.4 [RFC8949] 5 array Bigfloat; see Section 3.4.4 [RFC8949] 6-15 Unassigned 16 COSE_Encrypt0 COSE Single Recipient Encrypted Data Object [RFC9052] 17 COSE_Mac0 COSE Mac w/o Recipients Object [RFC9052] 18 COSE_Sign1 COSE Single Signer Data Object [RFC9052] 19 COSE_Countersignature COSE standalone V2 countersignature [RFC9338] 20 Unassigned 21 (any) Expected conversion to base64url encoding; see Section 3.4.5.2 [RFC8949] 22 (any) Expected conversion to base64 encoding; see Section 3.4.5.2 [RFC8949] 23 (any) Expected conversion to base16 encoding; see Section 3.4.5.2 [RFC8949] 24 byte string Encoded CBOR data item; see Section 3.4.5.1 [RFC8949] 25 unsigned integer reference the nth previously seen string [http://cbor.schmorp.de/stringref][Marc_A._Lehmann] 26 array Serialised Perl object with classname and constructor arguments [http://cbor.schmorp.de/perl-object][Marc_A._Lehmann] 27 array Serialised language-independent object with type name and constructor [http://cbor.schmorp.de/generic-object][Marc_A._Lehmann] arguments 28 multiple mark value as (potentially) shared [http://cbor.schmorp.de/value-sharing][Marc_A._Lehmann] 29 unsigned integer reference nth marked value [http://cbor.schmorp.de/value-sharing][Marc_A._Lehmann] 30 array Rational number [http://peteroupc.github.io/CBOR/rational.html][Peter_Occil] 31 Undefined (0xf7) Absent value in a CBOR Array [https://github.com/svaarala/cbor-specs/blob/master/cbor-absent-tag.rst][Sami_Vaarala] 32 text string URI; see Section 3.4.5.3 [RFC8949] 33 text string base64url; see Section 3.4.5.3 [RFC8949] 34 text string base64; see Section 3.4.5.3 [RFC8949] 35 UTF-8 string Regular expression; see Section 2.4.4.3 [RFC7049] 36 text string MIME message; see Section 3.4.5.3 [RFC8949] 37 byte string Binary UUID ([RFC4122, Section 4.1.2]) [https://github.com/lucas-clemente/cbor-specs/blob/master/uuid.md][Lucas_Clemente] 38 array Language-tagged string [RFC9290, Appendix A] 39 multiple Identifier [https://github.com/lucas-clemente/cbor-specs/blob/master/id.md][Lucas_Clemente] 40 array of two arrays Multi-dimensional Array, row-major order [RFC8746] [1] 41 array Homogeneous Array [RFC8746] 42 byte string IPLD content identifier [https://github.com/ipld/cid-cbor/][Volker_Mische] 43 text string YANG bits datatype; see Section 6.7. [RFC9254] 44 text string YANG enumeration datatype; see Section 6.6. [RFC9254] 45 unsigned integer or YANG identityref datatype; see Section 6.10. [RFC9254] text string 46 unsigned integer or YANG instance-identifier datatype; see Section 6.13. [RFC9254] text string or array 47 unsigned integer YANG Schema Item iDentifier (sid); see Section 3.2. [RFC9254] 48-51 Unassigned 52 byte string or array IPv4, [prefixlen,IPv4], [IPv4,prefixpart] [RFC9164] 53 Unassigned 54 byte string or array IPv6, [prefixlen,IPv6], [IPv6,prefixpart] [RFC9164] 55-60 Unassigned 61 CBOR Web Token (CWT) CBOR Web Token (CWT) [RFC8392][Michael_B._Jones] 62 Unassigned 63 byte string Encoded CBOR Sequence [RFC8742] [draft-bormann-cbor-notable-tags-02, Section 2.1] 64 byte string uint8 Typed Array [RFC8746] 65 byte string uint16, big endian, Typed Array [RFC8746] 66 byte string uint32, big endian, Typed Array [RFC8746] 67 byte string uint64, big endian, Typed Array [RFC8746] 68 byte string uint8 Typed Array, clamped arithmetic [RFC8746] 69 byte string uint16, little endian, Typed Array [RFC8746] 70 byte string uint32, little endian, Typed Array [RFC8746] 71 byte string uint64, little endian, Typed Array [RFC8746] 72 byte string sint8 Typed Array [RFC8746] 73 byte string sint16, big endian, Typed Array [RFC8746] 74 byte string sint32, big endian, Typed Array [RFC8746] 75 byte string sint64, big endian, Typed Array [RFC8746] 76 byte string (reserved) [RFC8746] 77 byte string sint16, little endian, Typed Array [RFC8746] 78 byte string sint32, little endian, Typed Array [RFC8746] 79 byte string sint64, little endian, Typed Array [RFC8746] 80 byte string IEEE 754 binary16, big endian, Typed Array [RFC8746] 81 byte string IEEE 754 binary32, big endian, Typed Array [RFC8746] 82 byte string IEEE 754 binary64, big endian, Typed Array [RFC8746] 83 byte string IEEE 754 binary128, big endian, Typed Array [RFC8746] 84 byte string IEEE 754 binary16, little endian, Typed Array [RFC8746] 85 byte string IEEE 754 binary32, little endian, Typed Array [RFC8746] 86 byte string IEEE 754 binary64, little endian, Typed Array [RFC8746] 87 byte string IEEE 754 binary128, little endian, Typed Array [RFC8746] 88-95 Unassigned 96 COSE_Encrypt COSE Encrypted Data Object [RFC9052] 97 COSE_Mac COSE MACed Data Object [RFC9052] 98 COSE_Sign COSE Signed Data Object [RFC9052] 99 Unassigned 100 Unsigned or negative Number of days since the epoch date 1970-01-01 [RFC8943] integer 101 array [uint, any] alternatives as given by the uint + 128; see Section 9.1 [draft-bormann-cbor-notable-tags-07] 102 Unassigned 103 array Geographic Coordinates [https://github.com/allthingstalk/cbor/blob/master/CBOR-Tag103-Geographic-Coordinates.md][Danilo_Vidovic] 104 multiple Geographic Coordinate Reference System WKT or EPSG number [draft-clarke-cbor-crs] 105-109 Unassigned 110 byte string, array, relative object identifier (BER encoding); SDNV [RFC6256] sequence [RFC9090] or map 111 byte string, array, object identifier (BER encoding) [RFC9090] or map 112 byte string, array, object identifier (BER encoding), relative to 1.3.6.1.4.1 [RFC9090] or map 113-119 Unassigned 120 multiple Internet of Things Data Point [https://github.com/allthingstalk/cbor/blob/master/CBOR-Tag120-Internet-of-Things-Data-Points.md][Danilo_Vidovic] 121-127 any alternatives 0..6, 1+1 encoding; see Section 9.1 [draft-bormann-cbor-notable-tags-07] 128-255 Unassigned 256 multiple mark value as having string references [http://cbor.schmorp.de/stringref][Marc_A._Lehmann] 257 byte string Binary MIME message [http://peteroupc.github.io/CBOR/binarymime.html][Peter_Occil] 258 array Mathematical finite set [https://github.com/input-output-hk/cbor-sets-spec/blob/master/CBOR_SETS.md][Alfredo_Di_Napoli] 259 map Map datatype with key-value operations (e.g. `.get()/.set()/.delete()`) [https://github.com/shanewholloway/js-cbor-codec/blob/master/docs/CBOR-259-spec--explicit-maps.md][Shane_Holloway] 260 byte string Network Address (IPv4 or IPv6 or MAC Address) (DEPRECATED in favor of 52 [http://www.employees.org/~ravir/cbor-network.txt][Ravi_Raju][RFC9164] and 54 for IP addresses) 261 map (IPAddress + Mask Network Address Prefix (IPv4 or IPv6 Address + Mask Length) (DEPRECATED [https://github.com/toravir/CBOR-Tag-Specs/blob/master/networkPrefix.md][Ravi_Raju][RFC9164] Length) in favor of 52 and 54 for IP addresses) 262 byte string Embedded JSON Object [https://github.com/toravir/CBOR-Tag-Specs/blob/master/embeddedJSON.md][Ravi_Raju] 263 byte string Hexadecimal string [https://github.com/toravir/CBOR-Tag-Specs/blob/master/hexString.md][Ravi_Raju] 264 array Decimal fraction with arbitrary exponent [http://peteroupc.github.io/CBOR/bigfrac.html][Peter_Occil] 265 array Bigfloat with arbitrary exponent [http://peteroupc.github.io/CBOR/bigfrac.html][Peter_Occil] 266 text string Internationalized resource identifier (IRI) [https://peteroupc.github.io/CBOR/iri.html][Peter_Occil] 267 text string Internationalized resource identifier reference (IRI reference) [https://peteroupc.github.io/CBOR/iri.html][Peter_Occil] 268 array Extended decimal fraction [https://peteroupc.github.io/CBOR/extended.html][Peter_Occil] 269 array Extended bigfloat [https://peteroupc.github.io/CBOR/extended.html][Peter_Occil] 270 array Extended rational number [https://peteroupc.github.io/CBOR/extended.html][Peter_Occil] DDoS Open Threat DDoS Open Threat Signaling (DOTS) signal channel object, as defined in 271 Signaling (DOTS) [RFC9132] [RFC9132] signal channel object 272 byte string Non-UTF-8 CESU-8 string [https://github.com/svaarala/cbor-specs/blob/master/cbor-nonutf8-string-tags.rst][Sami_Vaarala] 273 byte string Non-UTF-8 WTF-8 string [https://github.com/svaarala/cbor-specs/blob/master/cbor-nonutf8-string-tags.rst][Sami_Vaarala] 274 byte string Non-UTF-8 MUTF-8 string [https://github.com/svaarala/cbor-specs/blob/master/cbor-nonutf8-string-tags.rst][Sami_Vaarala] 275 map (major type 5) Map contains only keys that are of type Text String (major type 3) [https://github.com/ecorm/cbor-tag-text-key-map][Emile_Cormier] 276 byte string ERIS binary read capability [http://purl.org/eris] 277 byte string Universal Geographical Area Description (GAD) shape; see Section 5 [TS 23.032][Mathew_Meins] 278 byte string Universal Geographical Area Description (GAD) description of velocity; [TS 23.032][Mathew_Meins] see Section 8 279-1000 Unassigned 1001 map extended time [draft-bormann-cbor-time-tag-01] 1002 map duration [draft-bormann-cbor-time-tag-01] 1003 map period [draft-bormann-cbor-time-tag-01] 1004 UTF-8 text string [RFC3339] full-date string [RFC8943] 1005-1009 Unassigned 1010 array: [id: text Object type identifier [draft-rundgren-cotx-04] string, obj: any] 1011-1039 Unassigned 1040 array of two arrays Multi-dimensional Array, column-major order [RFC8746] [1] 1041-1279 Unassigned 1280-1400 any alternatives 7..127, 1+2 encoding; see Section 9.1 [draft-bormann-cbor-notable-tags-07] 1401-22097 Unassigned 22098 multiple hint that indicates an additional level of indirection [http://cbor.schmorp.de/indirection][Marc_A._Lehmann] 22099-25440 Unassigned Array containing at 25441 most one array Capture [3] [https://github.com/japhb/cbor-specs/blob/main/capture.md][Geoffrey_Broadwell] followed by at most one map 25442-32767 Unassigned 32768 unsigned integer Identifier for a FHIR constant [Stefan_Genchev] template/32768 32769 multiple External reference [https://gitlab.com/Hawk777/cbor-specs/-/blob/main/external-reference.md][Christopher_Head] 32770-42599 Unassigned 42600 map A confidentiality clearance. The key value pairs of the map are defined [Aidan_Murdock] template/42600 in ADatP-4774.4 A metadata binding. The elements of the array are defined in 42601 array AdatP-4778.5. The tag is also used as part of the magic number in on-disk [Aidan_Murdock] template/42601 detached and encapsulating bindings. 42602 map A collection of NCMS metadata elements. The key value pairs of the map [Aidan_Murdock] template/42602 are defined in AdatP-5636.4 42603-42999 Unassigned 43000 array Single complex number: array elements are real (I) and imaginary (Q) [Saajan_Chana] template/43000 components Array of complex numbers in interleaved form: complex value k is stored 43001 array with real (I) part at array index 2k and imaginary (Q) part at index (2k [Saajan_Chana] template/43001 + 1) 43002-49999 Unassigned 50000 integer PlatformV_IS_ID [https://github.com/arthurwangtz/platformv-cbor][Wang_Tongzhou] 50001 text string PlatformV_IS_NAME [https://github.com/arthurwangtz/platformv-cbor][Wang_Tongzhou] 50002 any PlatformV_IS_VALUE [https://github.com/arthurwangtz/platformv-cbor][Wang_Tongzhou] 50003 array PlatformV_HAS_COMPOSITE_VALUE [https://github.com/arthurwangtz/platformv-cbor][Wang_Tongzhou] 50004 array PlatformV_HAS_MAPPED_VALUE [https://github.com/arthurwangtz/platformv-cbor][Wang_Tongzhou] 50005 array PlatformV_HAS_OBJ_ID [https://github.com/arthurwangtz/platformv-cbor][Wang_Tongzhou] 50006 array PlatformV_HAS_OBJ_TAG [https://github.com/arthurwangtz/platformv-cbor][Wang_Tongzhou] 50007 array PlatformV_HAS_CHILD [https://github.com/arthurwangtz/platformv-cbor][Wang_Tongzhou] 50008 array PlatformV_HAS_PROPERTY [https://github.com/arthurwangtz/platformv-cbor][Wang_Tongzhou] 50009 array PlatformV_HAS_META [https://github.com/arthurwangtz/platformv-cbor][Wang_Tongzhou] 50010 array PlatformV_HAS_EVENT [https://github.com/arthurwangtz/platformv-cbor][Wang_Tongzhou] 50011 array PlatformV_HAS_ACTION [https://github.com/arthurwangtz/platformv-cbor][Wang_Tongzhou] 50012 integer PlatformV_IS_TYPE [https://github.com/arthurwangtz/platformv-cbor][Wang_Tongzhou] 50013-55798 Unassigned 55799 (any) Self-described CBOR; see Section 3.4.6 [RFC8949] 55800 tagged byte string indicates that the file contains CBOR Sequences [RFC9277] 55801 tagged byte string indicates that the file starts with a CBOR-Labeled Non-CBOR Data label. [RFC9277] 55802-56499 Unassigned 56500 array (major type 4) Compressed byte string [https://github.com/dectris/documentation/blob/main/cbor/dectris-compression-tag.md][Kal_Conley] 56501-57341 Unassigned Identify and define a set of record structures (each a sequence of 57342 array property names) that can be referenced as tags in the included value (and [https://github.com/kriszyp/cbor-records][Kris_Zyp] the scope for the record tag definitions) Identify and define a record structure (a sequence of property names), 57343 array and use that record structure definition to interpret the included [https://github.com/kriszyp/cbor-records][Kris_Zyp] values. 57344-57599 array References a defined record structure, using that referenced record [https://github.com/kriszyp/cbor-records][Kris_Zyp] definition to interpret the included values. 57600-59999 Unassigned 60000 array The tagged CBOR array contains attestation evidence data with an Intel [Shanwei_Cen] template/60000 TEE quote. 60001 array The tagged CBOR array contains attestation evidence data with an Intel [Shanwei_Cen] template/60001 TEE report. 60002 array The tagged CBOR array contains attestation evidence data with an Intel [Shanwei_Cen] template/60002 SGX report. 60003-65534 Unassigned 65535 (none valid) always invalid; see Section 10.1 [draft-bormann-cbor-notable-tags-02] 65536-79999 Unassigned 80000-80099 byte string, array or Private tags as suggested in [Tony_Putman] template/80000-80099 map [https://mailarchive.ietf.org/arch/msg/cbor/NJlskB63pjXFt5a6S37tiwJBbCM]. 80100-15309735 Unassigned 15309736 map (major type 5) RAINS Message [https://britram.github.io/rains-prototype][Brian_Trammell] 15309737-1330664269 Unassigned 1330664270 byte-string A CBOR encoded Openswan configuration file, as stored on disk for unit [Michael_Richardson][Samir_Hussain] template/1330664270 test cases. 1330664271-1398229315 Unassigned 1398229316 map Concise Software Identifier (CoSWID) [RFC-ietf-sacm-coswid-24] 1398229317-1668546816 Unassigned byte string or any 1668546817-1668612095 CBOR data item (see the representation of content-format ct < 65025 is indicated by tag [RFC9277] Appendix B of number TN(ct) = 0x63740101 + (ct / 255) * 256 + ct % 255 [RFC9277]) 1668612096-1701996914 Unassigned 1701996915 array Array of content-addressed blocks and ERIS read capabilities [Endo_Renberg] template/1701996915 1701996916-4294967294 Unassigned 4294967295 (none valid) always invalid; see Section 10.1 [draft-bormann-cbor-notable-tags-02] 4294967296 map Intel FPGA SPDM Manifest [Andrew_Draper] template/4294967296 4294967297-18446744073709551614 Unassigned 18446744073709551615 (none valid) always invalid; Section 10.1 [draft-bormann-cbor-notable-tags-02] Contact Information ID Name Contact URI Last Updated [Aidan_Murdock] Aidan Murdock mailto:aidan.murdock&ncia.nato.int 2022-05-24 [Alfredo_Di_Napoli] Alfredo Di Napoli mailto:alfredo.dinapoli&iohk.io 2017-08-25 [Andrew_Draper] Andrew Draper mailto:andrew.draper&intel.com 2021-12-10 [Brian_Trammell] Brian Trammell mailto:ietf&trammell.ch 2016-08-17 [Christopher_Head] Christopher Head mailto:chead&chead.ca 2022-12-28 [Danilo_Vidovic] Danilo Vidovic mailto:cbor&allthingstalk.com 2018-04-17 [Emile_Cormier] Emile Cormier mailto:emile.cormier.jr&gmail.com 2020-03-30 [Endo_Renberg] Endo Renberg mailto:pukkamustard&posteo.net 2022-09-12 [Geoffrey_Broadwell] Geoffrey Broadwell mailto:gjb&sonic.net 2021-11-09 [Kal_Conley] Kal Conley mailto:kal.conley&dectris.com 2022-08-26 [Kris_Zyp] Kris Zyp mailto:kriszyp&gmail.com 2022-05-23 [Lucas_Clemente] Lucas Clemente mailto:lucas&clemente.io 2014-07-01 [Marc_A._Lehmann] Marc A. Lehmann mailto:cbor&schmorp.de 2013-11-26 [Mathew_Meins] Mathew Meins mailto:mm&blackhelicopters.net 2021-02-01 [Michael_B._Jones] Michael B. Jones mailto:mbjµsoft.com 2018-05-04 [Michael_Richardson] Michael Richardson mailto:mcr&xelerance.com 2021-01-25 [Peter_Occil] Peter Occil mailto:poccil14&gmail.com 2018-11-09 [Ravi_Raju] Ravi Raju mailto:ravir&employees.org 2018-03-06 [Saajan_Chana] Saajan Chana mailto:saajan.chana&cambridgeconsultants.com 2022-07-20 [Sami_Vaarala] Sami Vaarala mailto:sami.vaarala&iki.fi 2020-03-18 [Samir_Hussain] Samir Hussain mailto:shussain&xelerance.com 2021-01-25 [Shane_Holloway] Shane Holloway mailto:shane.holloway&ieee.org 2018-10-25 [Shanwei_Cen] Shanwei Cen mailto:shanwei.cen&intel.com 2023-01-12 [Stefan_Genchev] Stefan Genchev mailto:stefan.genchev&tum.de 2022-12-09 [Tony_Putman] Tony Putman mailto:anthony.putman&dyson.com 2023-04-26 [Volker_Mische] Volker Mische mailto:volker&protocol.ai 2019-08-23 [Wang_Tongzhou] Wang Tongzhou mailto:tongzhou.wang&siemens.com 2022-10-20 Footnote [1] second element of outer array in data item is native CBOR array (major type 4) or Typed Array (one of Tag 64..87) Licensing Terms