| Everyday help | Chat is designed for quick questions, search, brainstorming, rewriting and a broad mix of ordinary tasks. GPT-5.5 Instant remains the fast default while harder work can move into GPT-5.6 reasoning. | Claude chat is a strong place for sustained discussion, close reading and iterative writing. Sonnet is usually the practical default before escalating to Opus for a genuinely difficult job. | Choose the product whose ordinary interaction style helps you think clearly, then escalate the model only when the work gives you a reason. | Can you describe what a better answer would change, or are you selecting a stronger model because the task merely feels important? |
| Research | Deep research lets you choose web, uploaded files and connected apps, review the proposed research plan, steer the run and receive a cited report with an activity history. | Research performs multiple searches across the web and connected internal context, following open questions as it works and returning citations that can be checked. | Use the source access, plan control and final report format that fit the decision. For a narrow current fact, normal search may be faster in either product. | Which sources are authoritative for this question, and what evidence would make you reject the report even when it reads well? |
| Long documents | ChatGPT can analyse uploaded files, use project context and combine file material with search or other tools. It suits work that may continue into data analysis, visuals or another output. | Claude is a natural starting point for close reading, comparison across a large source pack and drafting that needs to preserve nuance across long material. | Start with Claude when the centre of gravity is careful reading and writing. Start with ChatGPT when the document is one input inside a broader research, data or multimodal workflow. | Which clauses, figures or sections are too important to trust to a summary, and how will you trace every consequential claim back to the source? |
| Finished office files | Work can create and edit documents, spreadsheets, presentations and reports from instructions, templates and source material, with progress steering and approval points. | Claude can create editable Word, Excel, PowerPoint and PDF files, while Cowork can coordinate file centred tasks and return finished outputs for review. | Choose by the source material, the file type, the tools already connected and the amount of supervision the task needs, not by which product produced the prettier first draft. | Does the final file preserve the right numbers, formulas, hierarchy, audience and organisational conventions when opened outside the AI product? |
| Interactive outputs | ChatGPT can produce visualisations and Sites in supported workflows, which fits a path from analysis or conversation into something shareable. | Artifacts are a prominent Claude workflow for building and refining standalone apps, tools, visualisations and content in a dedicated workspace. | Start with Claude when the interactive object itself is the work. Start with ChatGPT when the object is one output from a wider research, data or agentic process. | Who will use the output, what could they misunderstand, and what needs testing beyond the happy path shown in the preview? |
| Ongoing context | Projects keep related chats, reference files and instructions together and can provide context to both Chat and Work across an evolving effort. | Claude Projects and Cowork projects keep task context, instructions and files together, with some local folder behaviour depending on the surface. | Choose the system that matches where the source material already lives and how the work will be shared, revisited and governed over time. | What information should remain valid next month, what will go stale, and who owns removing or replacing outdated context? |
| Longer agentic work | Work is built for multi step knowledge work, connected apps and finished deliverables. It can run once, on a schedule or in response to a trigger, depending on access and settings. | Cowork can work across selected files, browser and apps, create outputs, use scheduled tasks and continue remotely, with capability varying by surface and permission. | Prefer the route with the narrowest permissions that can finish the job and the clearest place for you to review, redirect and approve consequential actions. | What may the agent read, what may it change, what must require approval, and what is the fastest safe way to stop or reverse the work? |
| Voice and visual context | ChatGPT combines voice with text, photos, visuals and search in the same conversation, which is useful while moving or when the physical context matters. | Claude accepts text and images and can analyse visual documents, but it is not the same live voice and camera centred experience. | Use ChatGPT when spoken interaction or live visual context is central. Use Claude when the image is evidence inside a careful reading or document task. | Could background noise, an unclear image or a private environment cause the model to misread or expose something important? |
| Choosing a model | ChatGPT separates fast everyday responses from GPT-5.6 reasoning settings and Pro. Higher effort should be earned by task complexity, not selected by habit. | Claude offers Sonnet for broad professional work and Opus for more demanding agentic or long horizon work, with effort controlling how much work the model spends. | Begin with the least expensive route likely to succeed, then escalate only after the output fails a named quality check or the task has consequences that justify a deeper pass. | Are you measuring answer quality, correction time and total task cost, or only noticing that the stronger option sounds more confident? |
| Privacy and permissions | Data handling depends on whether you are using consumer ChatGPT, a managed workspace, the API, connected apps or local Work. The product name alone does not settle it. | Consumer Claude, commercial Claude, cloud platforms and Cowork have different retention and access conditions. Cowork risk grows with what it can read and what it can do. | Choose only after checking the exact account, workspace, surface, connection and retention rules that govern the real material. | Would you still approve this workflow after listing every file, application, person and external system the AI could touch? |