Quick answer: A Claude Project is a reusable workspace for related chats. Create a project, add the documents or text every chat should know to Project knowledge, write clear Project instructions, and then start separate chats for individual tasks. A chat does not automatically inherit facts from another chat unless those facts are also placed in project knowledge.
Projects are useful for work that continues across multiple conversations: research, content production, software development, study, client work, or a long-running personal project. They reduce repeated setup, but they work best when the knowledge base is curated rather than treated as unlimited storage.
Who can use Claude Projects?
Anthropic currently describes Projects as available on paid Claude plans. Team and Enterprise workspaces can also apply organization visibility and sharing controls. Availability and limits can change, so check your account rather than relying on an old plan comparison.
If you are choosing a paid plan, read Claude Pro vs Max and compare Claude Pro App Store prices by country.
How to create a Claude Project
- Open Claude and go to the Projects section in the left sidebar, or visit claude.ai/projects.
- Select New Project.
- Give the project a clear name and description.
- If your work account offers visibility settings, choose whether the project is private or available to people in your organization.
- Create the project, then add knowledge and instructions before starting the main work.
Anthropic notes that the project name and description are for organization; Claude does not use those fields as task context. Put behavior rules in Project instructions and factual material in Project knowledge.
Add information to Project knowledge
Project knowledge is the reusable context available to chats inside the project. From the project page:
- Find the knowledge area on the right side of the project.
- Select the plus button to add content.
- Upload relevant documents, text files or code snippets.
- Wait for Claude to process the material.
- Start a new project chat and ask a small verification question to confirm the important material is being used correctly.
Good project knowledge includes a product brief, style guide, approved facts, requirements, glossary, research papers, code documentation or a decision log. Temporary instructions for one task usually belong in that task’s chat instead.
Write effective Project instructions
Select Set project instructions, enter the rules that should apply to every chat in the project, and save them. Useful instructions are short, specific and testable.
A practical structure is:
Role: Act as an editor for this project.
Audience: Write for non-technical subscribers.
Sources: Prefer project knowledge; identify missing evidence.
Output: Start with a direct answer, then steps and caveats.
Restrictions: Do not invent prices, limits, testing or quotations.
Avoid putting long reference material in instructions. Upload it as knowledge instead. Instructions should describe how Claude should work; knowledge should contain what Claude should know.
Project knowledge vs chat attachments
The location of a file changes how it is used:
- Project knowledge: reusable across chats in the project.
- Chat attachment: intended for that individual conversation.
- Text in another chat: not automatically shared with a new chat.
This distinction explains many “Claude forgot my document” reports. If several chats need the same source, add it to project knowledge instead of uploading it separately to one conversation.
Claude Project file limits
Anthropic’s current document guidance lists a 30 MB per-file limit for both chat uploads and project knowledge. Project knowledge can contain an unlimited number of files, but the extracted content must still fit the available context. When project knowledge approaches the context limit, Claude can automatically use retrieval-augmented generation, or RAG, to expand usable capacity.
Anthropic says enhanced project knowledge can expand capacity by up to 10 times, but that does not mean every file is read in full for every response. Retrieval selects material considered relevant to the current question.
Supported document types currently include PDF, DOCX, CSV, TXT, HTML, ODT, RTF, EPUB, JSON and, when the analysis tool is enabled, XLSX. Non-PDF documents are generally processed as text. PDF visual handling depends on the model and document length. See Claude file upload limits and fixes for current details.
How to organize chats inside a project
Use one chat per task or decision rather than keeping an endless conversation:
- one chat for the research outline;
- one for source review;
- one for a first draft;
- one for fact-checking;
- one for the final revision.
When a chat produces an approved decision or reusable fact, add a concise version to project knowledge or update the source document. Otherwise a later chat will not automatically know the decision.
A reliable Claude Project workflow
- Define the outcome. Decide what the project should repeatedly help you produce.
- Curate the sources. Upload only current, authoritative material.
- Write project instructions. Specify audience, format, sourcing and restrictions.
- Test retrieval. Ask where a key fact comes from and confirm the answer against the file.
- Separate tasks into chats. Keep each conversation focused.
- Promote decisions to knowledge. Save approved facts so future chats can use them.
- Review the knowledge base. Remove or replace obsolete material so conflicting versions do not compete.
Common Claude Projects problems
The Projects option is missing
Confirm that you are signed into the intended account and that the account has a paid plan that includes Projects. Workspaces may also apply administrator controls.
Claude ignores a file in another chat
The file may have been attached only to one conversation. Add reusable material to Project knowledge and start a new test chat.
Claude uses the wrong version of a document
Remove obsolete copies, give files unambiguous names, and state which version is authoritative. Conflicting documents create a source-selection problem, not merely a prompting problem.
Project instructions are not followed consistently
Shorten the instructions, remove contradictions and turn vague preferences into explicit rules. A chat-level request can also conflict with project instructions, so inspect both.
A large knowledge base gives weak answers
Split broad projects into narrower workspaces, use descriptive files, and ask questions that name the relevant document or topic. RAG expands capacity but still depends on retrieval relevance.
Privacy and sharing considerations
Do not upload confidential, regulated or client material unless you are authorized to use it with the selected account and workspace. For Team or Enterprise projects, confirm visibility before adding knowledge. Review project content before inviting collaborators or using generated output outside the organization.
Claude Projects FAQ
Does every chat share the same project history?
No. Anthropic says context is not shared across chats unless the information is added to the project knowledge base.
Are Project instructions the same as knowledge?
No. Instructions control how Claude should respond across the project. Knowledge supplies reusable facts and documents.
Can I upload unlimited files?
Anthropic currently describes the file count for project knowledge as unlimited, but total extracted content and context limits still apply. Individual files are limited to 30 MB.
What happens when the project becomes too large?
Claude can automatically switch to RAG when project knowledge approaches the context limit. It retrieves relevant material instead of loading every file into every response.
Official sources
- Anthropic: How to create and manage Projects
- Anthropic: What are Projects?
- Anthropic: Supported documents and file limits
Last verified: July 26, 2026. Project availability, file handling and interface labels can change by plan and workspace.
Browse more tutorials in Claude Help or the HiseHub How-To library.