A standalone general assistant and a managed Microsoft 365 assistant, compared for document work, workspace access, controls, and full cost. This guidance is based on company pages linked from the profiles below.
You want a standalone assistant for file analysis, data, images, and research, with separately enabled Microsoft connections.
Look elsewhere if: You need embedded PDF images analyzed outside ChatGPT Enterprise, or a dedicated document editor with tightly controlled revision and handoff features; other plans use text-only PDF retrieval and discard embedded images.
You want one assistant inside your organization’s Word, Excel, PowerPoint, Outlook, and Teams.
Look elsewhere if: You lack the required Microsoft 365 plan, want a standalone tool, or need documented file limits and OCR behavior before choosing. The linked Microsoft pages publish no hard upload-size cap and do not establish scanned-PDF or OCR behavior, so treat both as unknown. Microsoft also warns that some long-document tasks in Word and PowerPoint may give less attention to the middle.
| Detail | ChatGPTOpenAI | Microsoft 365 CopilotMicrosoft |
|---|---|---|
| Made for | General assistant | Work suite |
| US price | Free; Go $8/mo (may include ads); Plus $20/mo; Pro from $100/mo (opens in a new tab) Full ChatGPT plan detailsA free plan is available. In the US, Go is $8 monthly and Plus is $20 monthly. Pro is $100 monthly for 5× Plus usage or $200 monthly for 20×. Go, Plus, and Pro are billed monthly only. ChatGPT Business standard seats are $25 per user monthly or $20 per user monthly when billed annually, with a two-seat minimum. Usage limits apply. | Paid add-on: first-year $18/user/mo annually + base plan (opens in a new tab) Full Microsoft 365 Copilot plan detailsCopilot Business is currently $18 per user monthly when paid yearly for the first year (regularly $21; offer ends September 30, 2026), or $25.20 with a monthly commitment. A qualifying Microsoft 365 Business plan is required. Microsoft says there is no trial for Microsoft 365 Copilot. As one US bundle, Microsoft 365 Business Standard with Copilot is $23.50 per user monthly, paid yearly, and includes Teams. Eligible Microsoft 365 business and enterprise customers get web-grounded Copilot Chat and Copilot in Outlook at no additional cost. Some eligible accounts receive an M365 Copilot (Basic) label, which provides standard access in Word, Excel, PowerPoint, and OneNote without the paid add-on; confirm the assigned label and admin settings. The paid add-on provides priority access, full work-data reasoning across meetings, email, chats, and files, and advanced agents. |
| Ways to use it | Web, macOS, Windows, iOS, Android | Web, Windows, iOS, Android, Microsoft 365 apps |
| Access | Cloud service with web, desktop, and mobile apps. | Managed Microsoft 365 service in Teams, Outlook, Word, Excel, PowerPoint, and other apps for eligible organizations and plans. |
| Where it runs | Online service from OpenAI. | Managed service inside eligible Microsoft 365 plans. |
| Profile evidence | Capabilities · Access · Limits · collected Aug 1, 2026 | Capabilities · Access · Limits · collected Aug 2, 2026 |
Microsoft 365 location alone does not decide it. ChatGPT can search permitted SharePoint and OneDrive files, Outlook mail and calendars, and Teams chats and channels through separately enabled apps; access depends on the app, plan, workspace settings, Microsoft Entra approval, and existing permissions. When actions are enabled, its Teams app can create chats and channels, send messages and replies, and work with Planner plans and tasks. Its add-ins can also create and edit directly in Excel and PowerPoint. Start with Microsoft 365 Copilot when you need one assistant inside your organization’s Word, Excel, PowerPoint, Outlook, and Teams. Start with ChatGPT when separate Microsoft connections plus its standalone file, data, image, and research workflows are enough.
Company sources: ChatGPT for PowerPoint (opens in a new tab) · ChatGPT for Excel and Google Sheets (opens in a new tab) · SharePoint app in ChatGPT (opens in a new tab) · Outlook Email and Calendar app for ChatGPT (opens in a new tab) · Microsoft Teams app for ChatGPT (opens in a new tab) · Microsoft 365 Copilot pricing (opens in a new tab)Check the actual file type, plan, and surface. ChatGPT accepts common document, presentation, spreadsheet, and text formats; conversation uploads are capped at 512 MB per file and 2 million tokens for text or document files. Only ChatGPT Enterprise supports visual retrieval inside PDFs. Other plans and non-PDF document files extract digital text and discard images. For work and school accounts, Microsoft publishes task-specific formats for Copilot Chat and other Microsoft 365 Copilot surfaces. Copilot Chat can answer questions about uploaded images and images embedded in Word or PowerPoint files, with limits depending on the subscription. These Microsoft pages do not publish an equivalent hard upload-size cap or establish scanned-PDF or OCR behavior, so treat both as unknown. In Word and PowerPoint, Microsoft warns that some long-document tasks may focus only on the beginning and give less attention to the middle; targeting a section or page range is not yet supported. The linked pages do not establish which product reads every decisive passage more reliably. Test one representative long, image-bearing or scanned file on the exact plan and surface, place known facts near the beginning, middle, and end, then verify all three against the original.
Company sources: ChatGPT file uploads (opens in a new tab) · Microsoft 365 Copilot supported file formats (opens in a new tab) · Microsoft 365 Copilot document length guidance (opens in a new tab) · Add content to Microsoft 365 Copilot Chat prompts (opens in a new tab)Use the current price row above. ChatGPT has standalone free and paid plans. Microsoft requires a qualifying Microsoft 365 base plan. An account labeled M365 Copilot (Basic) has standard access in Word, Excel, PowerPoint, and OneNote without the paid add-on; Copilot Chat (Basic) does not. The paid add-on provides priority access, full work-data reasoning, and advanced agents. Confirm the account's assigned label and admin settings.
Company sources: Microsoft 365 Copilot license labels (opens in a new tab) · Copilot Chat with and without an add-on (opens in a new tab)For individual ChatGPT services, OpenAI may use chats and uploads for training unless the user opts out; Business and Enterprise inputs and outputs are not used for training by default. ChatGPT Search may rewrite a prompt into targeted queries sent to third-party search providers; if Memory is enabled, relevant memories may inform those queries. Microsoft says Copilot prompts, responses, and Graph data are not used to train foundation models; prompts and responses are stored as Copilot activity history under Microsoft 365 retention controls. When web search is enabled, it sends Bing a short query derived from the prompt or uploaded file; administrators can disable web search, and users can inspect the query and cited pages. For Word's automatic summaries, Microsoft says Copilot considers the whole document but does not always cite later content. If passage-level traceability matters, use the same representative document in both products and verify material claims against the original; the linked company pages do not establish which is more reliable.
Company sources: How OpenAI uses data to improve models (opens in a new tab) · ChatGPT Search data sharing (opens in a new tab) · Data, privacy, and security for Microsoft 365 Copilot (opens in a new tab) · Web search in Microsoft 365 Copilot (opens in a new tab) · Create a summary of your document with Copilot in Word (opens in a new tab)