Which AI assistant works in every Windows program?

Zack KI reads copyable text from most apps. Protected fields and apps running as administrator can block this. You can use a screen capture instead.

8 AI assistants for Windows compared

In short

Zack KI handles questions and text editing from your Windows apps. The table compares alternatives for Microsoft 365, translation and corrections as you type.

Overview by task

Tool	Best for	How it starts	Limits
Zack KI	Questions, rewriting and corrections from any app; files, screenshots, web search with sources	Alt+1 with selection; Alt+3 and Alt+4 replace text directly	Windows only; no live underlining while you type
ChatGPT Windows app	Long conversations in your ChatGPT account across devices	Alt+Space companion window	Taking over selected text is documented for macOS only
Microsoft Copilot	Microsoft 365 data in your organisation; Copilot Vision	Copilot key or Win+C	Click to Do needs a Copilot+ PC
Grammarly	Live suggestions while you type, including German	Works inside the text field	Not a general chat about files or screenshots
DeepL with DeepL Write	Translation and polishing	Ctrl+C+C translates the selection	Focus on translation and style
Raycast for Windows	Launcher with Quick AI that inserts into the previous app	Root search, then Tab	AI requires a paid plan; selected text is added manually
PowerToys Advanced Paste	Free clipboard actions with your own key or a local model	Win+Shift+V	Works on the clipboard; AI is off by default
Writing Tools (open source)	Free rewriting with Gemini, Ollama or other APIs	Ctrl+Space	You configure the model provider yourself