From the studio behind Constitutional AI and Claude Code, the assistant most often picked for long-form writing, careful analysis, and software development. Reputation for clear answers and a measured tone.
The most widely used title on the shelf. Strong general capability across conversation, image generation, voice, and a deep ecosystem of custom GPTs built by third parties.
Google's flagship AI assistant. Tight integration with Search, Workspace, Android, and YouTube, plus very large context windows and strong multimodal handling across text, images, and video.
Microsoft's assistant for the office workflow. Strongest fit when work happens inside Word, Excel, Outlook, Teams, and the rest of Microsoft 365. Also available as a free standalone chat product.
| Spec | Claude | ChatGPT | Gemini | Copilot |
|---|---|---|---|---|
| Studio | Anthropic | OpenAI | Microsoft | |
| Strong On | Writing + Code | Ecosystem | Google Apps | MS Office |
| Free Tier | Yes | Yes | Yes | Yes |
| Pro Plan | ~$20 | ~$20 | ~$20 | ~$20 |
| Higher Tier | Max | Pro | AI Ultra | 365 add-on |
| Image Gen | via tools | built in | built in | built in |
| Voice Mode | via app | advanced | via app | via app |
| Office Suite | Excel beta | via plugins | Workspace | 365 native |
| Mobile App | iOS + Android | iOS + Android | iOS + Android | iOS + Android |
| API Access | Yes | Yes | Yes | Yes |
No single title fits every viewer. Claude tends to land best for careful writing and coding. ChatGPT has the widest ecosystem and image generation built in. Gemini shines when work lives in Google Workspace. Copilot is the natural pick inside Microsoft 365. All four offer free tiers. Try a couple before you settle.