XEP-xxxx: Emoji Markup

Abstract
This specification leverages Message Markup (XEP-0394) XEP-0394: Message Markup <https://xmpp.org/extensions/xep-0394.html>. and Stateless file sharing (XEP-0447) XEP-0447: Stateless file sharing <https://xmpp.org/extensions/xep-0447.html>. (or Stateless Inline Media Sharing (XEP-0385) XEP-0385: Stateless Inline Media Sharing (SIMS) <https://xmpp.org/extensions/xep-0385.html>.) to send custom emojis
Authors
  • Snit Guckfung
  • Sigrid Einarsson
Copyright
© 2026 – 2026 XMPP Standards Foundation. SEE LEGAL NOTICES.
Status

ProtoXEP

WARNING: This document has not yet been accepted for consideration or approved in any official manner by the XMPP Standards Foundation, and this document is not yet an XMPP Extension Protocol (XEP). If this document is accepted as a XEP by the XMPP Council, it will be published at <https://xmpp.org/extensions/> and announced on the <standards@xmpp.org> mailing list.
Type
Standards Track
Version
0.0.3 (2026-04-05)
Document Lifecycle
  1. Experimental
  2. Proposed
  3. Stable
  4. Final

1. Introduction

Many legacy platforms allow users to create and send custom emojis in place of the ones supported by Unicode, allowing users a wider range of expression when chatting. This specification provides a way for users to send custom emojis using a custom Message Markup (XEP-0394) [1] element containing Bits of Binary (XEP-0231) [4] data.

2. Discovering Support

Implementations which support custom emoji markup MUST advertise 'urn:xmpp:markup:emoji:0' via Entity Capabilities (XEP-0115) [5] and Service Discovery (XEP-0030) [6].

3. Use Cases

To send a custom emoji, implementations use a custom <emoji /> element qualified with the 'urn:xmpp:markup:emoji:0' namespace inside a Message Markup (XEP-0394) [1] <span /> element as a child of a Message Markup (XEP-0394) [1] <markup /> element, with a media element (either Stateless file sharing (XEP-0447) [2] <file-sharing /> or Stateless Inline Media Sharing (XEP-0385) [3] <media-sharing />) as a sibling of the <markup /> element. The <span /> MUST contain a 'start' and 'end' range which marks the range of text to replace with the custom emoji. If the 'start' and 'end' contain the same index, the emoji MUST be inserted at that index without replacing any text. The <emoji /> MAY contain a 'name' attribute containing the name of the emoji, but it MUST include one or more Use of Cryptographic Hash Functions in XMPP (XEP-0300) [7] <hash /> elements to identify the specific emoji in one of the media elements.

Example 1. User sends a custom emoji
<message from='romeo@montague.lit' to='juliet@shakespeare.lit' type='chat'>
    <body>To be, or not to be, that is the question 🤔</body>
    <markup xmlns='urn:xmpp:markup:0'>
        <span start='42' end='43'>
            <emoji xmlns='urn:xmpp:markup:emoji:0' name='pondering'>
                <hash xmlns='urn:xmpp:hashes:2' algo='sha3-256'>ENeyvkxcfv8dmL4HBrF3JU1OX1BfpNV3YbhlEb20ReU=</hash>
            </emoji>
        </span>
    </markup>
    <file-sharing xmlns='urn:xmpp:sfs:0'>
        <file xmlns='urn:xmpp:file:metadata:0'>
            <media-type>image/png</media-type>
            <name>pondering</name>
            <size>6129</size>
            <width>64</width>
            <height>64</width>
            <hash xmlns='urn:xmpp:hashes:2' algo='sha3-256'>ENeyvkxcfv8dmL4HBrF3JU1OX1BfpNV3YbhlEb20ReU=</hash>
            <hash xmlns='urn:xmpp:hashes:2' algo='id-blake2b256'>QdJufo3MnaEPCK/2Q8fCiX3FutiQej6uHg5HaCliheY=</hash>
        </file>
        <sources>
            <url-data xmlns='http://jabber.org/protocol/url-data' target='https://download.montague.lit/4a771ac1-f0b2-4a4a-9700-f2a26fa2bb67/pondering.png' />
        </sources>
    </file-sharing>
</message>
Example 2. User sends multiple custom emojis in a message
<message from='romeo@montague.lit' to='juliet@shakespeare.lit' type='chat'>
    <body>Look at this funny image I found! :laughing: I wonder what it means? :pondering:</body>
    <markup xmlns='urn:xmpp:markup:0'>
        <span start='34' end='44'>
            <emoji xmlns='urn:xmpp:markup:emoji:0' name='laughing'>
                <hash xmlns='urn:xmpp:hashes:2' algo='sha3-256'>jMbLbIw1lfDhNVrE1wtB8C1R94OXKbyq/i8DUmHiHs8=</hash>
                <hash xmlns='urn:xmpp:hashes:2' algo='id-blake2b256'>a5wIaBMtKT+Rs4TSc0C4ciWb5bmA3GCBv3xIUBxpKGA=</hash>
            </emoji>
        </span>
        <span start='69' end='80'>
            <emoji xmlns='urn:xmpp:markup:emoji:0' name='pondering'>
                <hash xmlns='urn:xmpp:hashes:2' algo='sha3-256'>ENeyvkxcfv8dmL4HBrF3JU1OX1BfpNV3YbhlEb20ReU=</hash>
                <hash xmlns='urn:xmpp:hashes:2' algo='id-blake2b256'>QdJufo3MnaEPCK/2Q8fCiX3FutiQej6uHg5HaCliheY=</hash>
            </emoji>
        </span>
    </markup>
    <file-sharing xmlns='urn:xmpp:sfs:0' id='emoji1'>
        <file xmlns='urn:xmpp:file:metadata:0'>
            <media-type>image/png</media-type>
            <name>laughing</name>
            <size>8391</size>
            <width>64</width>
            <height>64</width>
            <hash xmlns='urn:xmpp:hashes:2' algo='sha3-256'>jMbLbIw1lfDhNVrE1wtB8C1R94OXKbyq/i8DUmHiHs8=</hash>
            <hash xmlns='urn:xmpp:hashes:2' algo='id-blake2b256'>a5wIaBMtKT+Rs4TSc0C4ciWb5bmA3GCBv3xIUBxpKGA=</hash>
        </file>
        <sources>
            <url-data xmlns='http://jabber.org/protocol/url-data' target='https://download.montague.lit/d51e8d71-98a3-4dd7-be64-cb4c778c90d2/laughing.png' />
        </sources>
    </file-sharing>
    <file-sharing xmlns='urn:xmpp:sfs:0' id='emoji2'>
        <file xmlns='urn:xmpp:file:metadata:0'>
            <media-type>image/png</media-type>
            <name>pondering</name>
            <size>6129</size>
            <width>64</width>
            <height>64</width>
            <hash xmlns='urn:xmpp:hashes:2' algo='sha3-256'>ENeyvkxcfv8dmL4HBrF3JU1OX1BfpNV3YbhlEb20ReU=</hash>
            <hash xmlns='urn:xmpp:hashes:2' algo='id-blake2b256'>QdJufo3MnaEPCK/2Q8fCiX3FutiQej6uHg5HaCliheY=</hash>
        </file>
        <sources>
            <url-data xmlns='http://jabber.org/protocol/url-data' target='https://download.montague.lit/16c8bc69-f4b2-4772-8db3-74fca5e2a275/pondering.png' />
        </sources>
    </file-sharing>
</message>

4. Business Rules

Many custom emojis can be adequately represented in terms of an existing Unicode emoji. Clients might find it useful to allow users to optionally specify a replacement emoji, which will improve the experience of users of clients which do not support custom emojis, with the name/shortcode of the emoji used only as a fallback. However, this specification makes no recommendation on the fallback text an implementation opts to use.

Implementations SHOULD expect to handle animated emojis, such as GIFs or animated PNGs. This could include either playing the animation or displaying the first frame.

Implementations might receive a file type which they do not or cannot support, in which case they MAY opt to ignore the emoji markup altogether.

5. Implementation Notes

Implementations MAY use sticker packs in Stickers (XEP-0449) [8] for emojis too

6. Accessibility Considerations

Implementations SHOULD provide a proper fallback for custom emojis, as well as including the 'name' attribute. This helps both users of unsupported clients as well as users who may not be able to view the emoji properly.

Implementations MAY post-process the file for color deficiency, epilepsy, or other accessiblity reasons. This could include slowing down playback or changing the saturation.

7. Security Considerations

Emojis are just media files. All the usual security risks of allowing users to send arbitrary media apply.

8. IANA Considerations

None.

9. XMPP Registrar Considerations

This specification defines the 'urn:xmpp:markup:emoji:0' namespace.

10. XML Schema

TODO.


Appendices

Appendix A: Document Information

Series
XEP
Number
xxxx
Publisher
XMPP Standards Foundation
Status
ProtoXEP
Type
Standards Track
Version
0.0.3
Last Updated
2026-04-05
Approving Body
XMPP Council
Dependencies
XMPP Core, XEP-0001, XEP-0030, XEP-0115, XEP-0300, XEP-0385, XEP-0394, XEP-0447
Supersedes
None
Superseded By
None
Short Name
NOT_YET_ASSIGNED

This document in other formats: XML  PDF

Appendix B: Author Information

Snit Guckfung
Email
snit@cock.li
JabberID
snit@isekai.rocks
Sigrid Einarsson
Email
techmetx11@disroot.org
JabberID
techmetx11@disroot.org

Copyright

This XMPP Extension Protocol is copyright © 1999 – 2024 by the XMPP Standards Foundation (XSF).

Permissions

Permission is hereby granted, free of charge, to any person obtaining a copy of this specification (the "Specification"), to make use of the Specification without restriction, including without limitation the rights to implement the Specification in a software program, deploy the Specification in a network service, and copy, modify, merge, publish, translate, distribute, sublicense, or sell copies of the Specification, and to permit persons to whom the Specification is furnished to do so, subject to the condition that the foregoing copyright notice and this permission notice shall be included in all copies or substantial portions of the Specification. Unless separate permission is granted, modified works that are redistributed shall not contain misleading information regarding the authors, title, number, or publisher of the Specification, and shall not claim endorsement of the modified works by the authors, any organization or project to which the authors belong, or the XMPP Standards Foundation.

Disclaimer of Warranty

## NOTE WELL: This Specification is provided on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, express or implied, including, without limitation, any warranties or conditions of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A PARTICULAR PURPOSE. ##

Limitation of Liability

In no event and under no legal theory, whether in tort (including negligence), contract, or otherwise, unless required by applicable law (such as deliberate and grossly negligent acts) or agreed to in writing, shall the XMPP Standards Foundation or any author of this Specification be liable for damages, including any direct, indirect, special, incidental, or consequential damages of any character arising from, out of, or in connection with the Specification or the implementation, deployment, or other use of the Specification (including but not limited to damages for loss of goodwill, work stoppage, computer failure or malfunction, or any and all other commercial damages or losses), even if the XMPP Standards Foundation or such author has been advised of the possibility of such damages.

IPR Conformance

This XMPP Extension Protocol has been contributed in full conformance with the XSF's Intellectual Property Rights Policy (a copy of which can be found at <https://xmpp.org/about/xsf/ipr-policy> or obtained by writing to XMPP Standards Foundation, P.O. Box 787, Parker, CO 80134 USA).

Visual Presentation

The HTML representation (you are looking at) is maintained by the XSF. It is based on the YAML CSS Framework, which is licensed under the terms of the CC-BY-SA 2.0 license.

Appendix D: Relation to XMPP

The Extensible Messaging and Presence Protocol (XMPP) is defined in the XMPP Core (RFC 6120) and XMPP IM (RFC 6121) specifications contributed by the XMPP Standards Foundation to the Internet Standards Process, which is managed by the Internet Engineering Task Force in accordance with RFC 2026. Any protocol defined in this document has been developed outside the Internet Standards Process and is to be understood as an extension to XMPP rather than as an evolution, development, or modification of XMPP itself.

Appendix E: Discussion Venue

The primary venue for discussion of XMPP Extension Protocols is the <standards@xmpp.org> discussion list.

Discussion on other xmpp.org discussion lists might also be appropriate; see <https://xmpp.org/community/> for a complete list.

Errata can be sent to <editor@xmpp.org>.

Appendix F: Requirements Conformance

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.

Appendix G: Notes

1. XEP-0394: Message Markup <https://xmpp.org/extensions/xep-0394.html>.

2. XEP-0447: Stateless file sharing <https://xmpp.org/extensions/xep-0447.html>.

3. XEP-0385: Stateless Inline Media Sharing (SIMS) <https://xmpp.org/extensions/xep-0385.html>.

4. XEP-0231: Bits of Binary <https://xmpp.org/extensions/xep-0231.html>.

5. XEP-0115: Entity Capabilities <https://xmpp.org/extensions/xep-0115.html>.

6. XEP-0030: Service Discovery <https://xmpp.org/extensions/xep-0030.html>.

7. XEP-0300: Use of Cryptographic Hash Functions in XMPP <https://xmpp.org/extensions/xep-0300.html>.

8. XEP-0449: Stickers <https://xmpp.org/extensions/xep-0449.html>.

Appendix H: Revision History

Note: Older versions of this specification might be available at https://xmpp.org/extensions/attic/

  1. Version 0.0.3 (2026-04-05)

    Changed the id attribute to refer to the first hash of the media element. Removed packs

    techmetx11
  2. Version 0.0.2 (2026-04-04)

    Added emoji packs, and switched to using SFS instead of just BoB

    techmetx11
  3. Version 0.0.1 (2026-03-08)

    First draft.

    snit

Appendix I: Bib(La)TeX Entry

@report{guckfung2026xepxxxx,
  title = {Emoji Markup},
  author = {Guckfung, Snit and Einarsson, Sigrid},
  type = {XEP},
  number = {xxxx},
  version = {0.0.3},
  institution = {XMPP Standards Foundation},
  url = {https://xmpp.org/extensions/xep-xxxx.html},
  date = {2026-03-08/2026-04-05},
}

END