Best AI for documents & proposals
A recommended ranking of AI for drafting proposals, reports and slides, compared by file support and language handling.
OpenAI's AI chat — the default choice, leading the global AI chatbot market share by a wide margin.
Google's AI chat — strong at search and Google-service integration; share is rising fast, especially in Japan.
Microsoft's assistant — its strength is integration with Windows and Office.
Anthropic's AI chat — praised for long-form writing, coding and careful prose; share is trending up.
Source: StatCounter (market share) + each official site (features, pricing) ／ Captured: 2026-10 （provisional） ／ Reference ranking by our editors
The current month is a provisional, month-to-date figure. Month-over-month change and risers/fallers are based on the latest completed month.
How to choose an AI for documents
Popularity is a start, but the points below are where tools actually differ for this use case.
1. The format you need
To produce slides directly, a deck generator such as Gamma fits; for outlines and first drafts of the text, an AI chat works well.
2. Can it read your existing files?
If you build on existing documents or figures, file-reading support is essential.
3. Working inside Office
To use AI directly inside Word, Excel and PowerPoint, an Office-integrated option such as Microsoft 365 Copilot is a candidate.
Features and pricing of every tool for documents
Including tools outside the ranking, this table lists the features and prices that matter for this use case.
| Tool | File reading | Japanese support | Free plan | Cheapest paid plan | Market share |
|---|---|---|---|---|---|
| ChatGPT | ○ | ○ | ○ | Go $8 | 68.4% |
| Google Gemini | ○ | ○ | ○ | Google AI Plus $4.99 | 18.5% |
| Perplexity | ○ | ○ | ○ | Pro $20 | 9.6% |
| Grok | ○ | ○ | ○ | Plus $8 | — |
| Microsoft Copilot | ○ | ○ | ○ | Microsoft 365 Premium $19.99 | 2.0% |
| Claude | ○ | ○ | ○ | Pro $20 | 1.5% |
| DeepSeek | ○ | ○ | ○ | — | <0.1% |
Dedicated documents tools compared
Besides AI chats, tools built specifically for this use case are also an option. Prices are each vendor's published list prices (USD). Where we could not confirm a USD price on the official page, we link to it instead of showing a number.
| Dedicated tool | Best at | Free plan | Cheapest paid plan |
|---|---|---|---|
| Canva Canva | A design tool with built-in image and text generation, combined with templates for decks and graphics. | ○ | Canva Pro $12/mo billed yearly |
| Gamma Gamma | Generates slides and documents from a prompt. Free users get 400 sign-up credits only (no refills). | ○ | Plus (see official pricing) |
| Napkin AI Napkin AI | Turns text into diagrams and visuals. Free visuals carry Napkin branding. | ○ | Plus $9/mo |
Source: Each vendor's official pricing page ／ Captured: 2026-10-17
Prices and free tiers of dedicated tools are reference values checked on each vendor's official page on 2026-10-17. Plans change often, so check the latest official information before subscribing.
Frequently asked questions
Which AI is the best for Documents?
Which AI can I use for documents for free?
For documents, should I choose an AI chat or a dedicated tool?
What is this ranking based on?
Other rankings by use case
⚠ These rankings are reference values based on public market-share data, web-traffic estimates and editorial research, and do not represent a complete count of every user of each AI tool. Rankings change with the measurement method (web-visit share vs. market share, etc.). Always check each official site for the latest information.