Overview
ISO/IEC 22121-2:2023 specifies design and specification requirements for on-screen keyboards with a direct touch interface (touchscreen keyboards). The document covers keyboards displayed on a screen - including those providing some audio feedback - and defines keyboard layouts, interaction methods, and conformance rules. It does not apply to virtual keyboards not shown on a screen, on-screen keyboards operated via an accessory (e.g., trackpad or remote), or physical keyboards with real/adaptable keys.
Key topics and technical requirements
Key technical areas addressed by the standard include:
- General requirements: character availability, single-finger/stylus and multi-finger input, and adjustable input parameters (long tap, double tap durations, touch pressure).
- Mapping of keyboard layouts: mapping alphabetic, numeric and non-graphic keys to on-screen layouts and row/key numbering systems.
- Toggle keys and commands: layout, location, locking/unlocking behavior and status indication for toggle keys (e.g., level/group/layout selection, dictation, deactivation).
- Associated characters: access and insertion methods (selection box, long tap) and accessible input-mode behavior.
- Context-dependent keyboard modes: behavior in numeric, email, URL/URI and preselected-value input fields.
- User customization: creating, switching, loading/saving and sharing keyboard layouts.
- Activation/deactivation: manual and automatic activation/deactivation rules and toggle location.
- Positioning and sizing: relative sizing, resizing rules, display constraints, rotation (landscape/portrait) and field overlap handling.
- Styling and visibility: contrast ratio, highlighting, colors/shading and key label sizing for legibility and accessibility.
- Conformance: rules for claiming and demonstrating conformance with the standard.
Applications and who uses it
This standard is intended for:
- Mobile OS and platform developers designing native touchscreen keyboards for smartphones, tablets and other touch-enabled devices.
- App developers and UX/UI designers implementing consistent, accessible on-screen keyboard behavior in applications.
- Keyboard and input method vendors creating customizable or localized on-screen keyboard layouts.
- Accessibility specialists and product managers ensuring keyboards meet usability and accessibility expectations across contexts (email, URLs, numeric entry).
- Device OEMs and integrators seeking standardized touch-input behavior, predictable toggle and sizing rules, and compliance documentation.
Benefits include improved usability, consistent input behavior across devices, easier localization of keyboard layouts, and better accessibility for diverse users.
Related standards
Refer to other parts of the ISO/IEC 22121 series and ISO/IEC standards on user interfaces and accessibility for complementary guidance on virtual keyboards and broader UI requirements.