AI autocomplete that works across your Mac

The operating system's Accessibility APIs expose the active editable field. A local language model receives limited nearby context and predicts a continuation. Cotabby displays that continuation without replacing what you have already written.

Cotabby is designed for native Mac applications, browser text fields, and many Electron applications. Common examples include Apple Mail, Notes, Messages, Slack, Discord, Gmail, Notion, Linear, and Google Docs.

Compatibility is not identical in every editor. Some web apps build custom text controls that expose less information to macOS. Cotabby intentionally stays out of password fields and terminals. Check the app compatibility reference for current limitations.

• Your draft does not need to cross the network for every suggestion.
• Suggestions continue without an internet connection.
• There is no per-token API bill or cloud rate limit.
• You can choose a model that fits the memory and speed of your Mac.

Local inference is not free of tradeoffs. A model occupies disk and memory, and larger models can respond too slowly for fluid typing. Apple Intelligence reduces setup on supported Macs; GGUF models provide more control on a broader range of systems.

Cotabby can suggest emoji shortcodes, correct recent typos, expand saved macros, use clipboard context, and adjust completion length. Those features share the same system-wide interaction: suggestions remain optional and disappear when you keep typing.

Context can improve relevance, but should be scoped. Cotabby reads the active text field and, when enabled, nearby screen text or clipboard contents. It does not keep a writing history or send telemetry. Read the permission and data-flow explanation.

Evaluate a product using repeatable work rather than a demo sentence:

• Measure accepted words during normal email, chat, and document writing.
• Check suggestion latency while other applications are open.
• Confirm how much text leaves the device and whether telemetry exists.
• Check daily limits, model restrictions, and long-term subscription cost.
• Verify behavior in the exact editors you use.

If Cotypist is your current reference point, see the detailed Cotabby and Cotypist comparison.

Install Cotabby, grant Accessibility and Input Monitoring, choose an engine, and begin typing. Press Tab for the next word, backtick for the complete suggestion, and Esc to dismiss. No account is required.

On a compatible Mac running macOS 26 or later, start with the Apple Intelligence engine. Otherwise, use Cotabby's recommended local model and test response time before experimenting with larger files.