--- title: "Give Claude a file to work on" url: https://aiguideson.com/courses/claude-for-beginners/give-claude-a-file-to-work-on/ course: "Claude for beginners" lesson: "3 of 5" minutes: 10 published: 2026-10-09 updated: 2026-10-09 author: "Jack Stovell" publisher: "Adapt Progress Evolve Limited" language: "en-GB" --- # Give Claude a file to work on Lesson 3 of 5 in [Claude for beginners](https://aiguideson.com/courses/claude-for-beginners/) · 10 minutes Claude can read a document you give it. In this lesson you’ll add a file to a chat, ask for a summary and a list of dates, and then check what Claude says is in it. ## You need - A Claude account - A document of your own that you’re happy to share with Claude: a newsletter, a letter or a report - About ten minutes A narrated walkthrough of this lesson is coming. The steps below cover everything in it. ## Steps ### Step 1: Check Claude can read your file Claude can work with PDF, DOCX, CSV, TXT, HTML, ODT, RTF, EPUB and JSON files, and XLSX if you’ve turned on code execution and file creation in your settings. It also takes JPEG, PNG, GIF and WebP images. For documents that aren’t PDFs, Claude reads the text only, so pictures inside them aren’t read. ![Anthropic’s help page “Upload files to Claude”, listing the supported document types and the supported image formats.](https://aiguideson.com/courses/claude-for-beginners/l3-upload-types.png) (screenshot captured 9 October 2026) 1. Documents Claude can read 2. Images it can look at Checkpoint: Your file’s in a format Claude can read. ### Step 2: Think before you share Anthropic recommends being thoughtful about sharing highly sensitive details, like financial information, health records, passwords and confidential documents. Use a document you’d be happy sharing, or cut the private parts out first. (Screenshot to come.) Checkpoint: You’ve picked a document that’s fine to share. ### Step 3: Add the file to a chat In a new chat, click the plus button in the lower left corner of the chat box, choose “Add files or photos”, then pick your file. You can also drag and drop a file into the chat. In a chat you can add up to 20 files, each up to 500MB. ![Anthropic’s help page “Upload files to Claude”, showing the steps to click the plus button, choose Add files or photos, or drag and drop.](https://aiguideson.com/courses/claude-for-beginners/l3-upload-how.png) (screenshot captured 9 October 2026) 1. Click + in the lower left of the chat box 2. Choose "Add files or photos" 3. Or drag and drop into the chat Checkpoint: Your file’s attached to the chat. ### Step 4: Ask for a summary and the dates Ask for the gist first, then the details you’d otherwise hunt for. We used a made-up newsletter from the Maple Street Allotment Society, and pasted its text under the prompt. You’ll attach your file instead. Claude sent back five bullets and a table of dates. The prompt (works in Claude): ```text Here is our allotment society’s autumn newsletter. Summarise it in five short bullet points, then list every date in it with what happens that day. ``` - “Five short bullet points” sets the length. - “Every date” asks for the details people miss. ![Our made-up newsletter on the left and Claude’s summary on the right: five bullet points and a table of nine dates.](https://aiguideson.com/courses/claude-for-beginners/l3-summary.png) (screenshot captured 9 October 2026) 1. The newsletter we gave it 2. Five bullets: the gist 3. Every date in one table Checkpoint: You’ve got a summary and a list of dates for your document. ### Step 5: Check it against the original Open your document next to the reply, and tick off each date. In our table the dates were right, but Claude put “March” above “31 January”, which is out of order. We asked it a follow-up about something the newsletter doesn’t say, the cost of a second plot. It said the newsletter has no prices, and it also pointed out its own ordering mistake. Feeling unsure about a detail you need? Ask “does it say…?”, and tell it to say so when it doesn’t. The prompt (works in Claude): ```text Does the newsletter say how much a second plot costs? If it does, quote the line. If it does not, say so. ``` - It asks about something we knew wasn’t in the document. - “If it does not, say so” gives Claude permission to say there’s no answer. (Screenshot to come.) Checkpoint: You’ve checked each date, and asked about one thing your document doesn’t say. ## Common problems ### Claude can’t open your file Check it’s one of the supported types. You can usually save a document as PDF or TXT first. ### The file is too big In a chat, files can be up to 500MB, and a PDF can have up to 1,000 pages. Anthropic suggests splitting larger documents into smaller sections. ### It missed a picture in your document For documents that aren’t PDFs, Claude reads the text only, so embedded pictures are not read. Add the picture as an image instead. Steps 1 and 3 are Anthropic’s public help page; step 4 is our own page built from the real prompt and reply. The chat screens are behind a login, so steps 3 and 5 have no chat screenshot yet. We pasted the newsletter’s text into the chat rather than attaching a file; the replies are in outputs/. ## Sources - [Claude Help Center: Upload files to Claude](https://support.claude.com/en/articles/8241126-upload-files-to-claude) (checked 2026-10-09) - [Claude Help Center: I would like to input sensitive data into my chats with Claude. Who can view my conversations?](https://support.claude.com/en/articles/8325621-i-would-like-to-input-sensitive-data-into-my-chats-with-claude-who-can-view-my-conversations) (checked 2026-10-09)