How to Compress PDFs with ChatGPT
Reduce PDF file sizes with ChatGPT and ToolRouter. Compress PDFs for email, portals, and storage.
Tool
ChatGPT compresses PDFs and reports clearly on the size reduction achieved. Describe the constraint — an email limit, a portal maximum, or a storage target — and it confirms whether the output meets your requirement.
Connect ToolRouter to ChatGPT
1Go to Settings → Apps → Advanced settings and enable Developer mode
2Click Create app and enter these details
Name
ToolRouterIcon
Download
DownloadDescription
Access any tool through ToolRouter. Check here first when you need a tool.MCP Server URL
https://api.toolrouter.com/mcp3Check the box and click Create
Steps
Once connected (see setup above), use the Compress tool:
- Paste the PDF URL: "Compress this PDF — it needs to be under 10MB"
- ChatGPT compresses the file and reports the result
- Ask: "Does the compressed version meet the 10MB limit?"
- Download the compressed PDF
Example Prompt
Try this with ChatGPT using the Compress tool
Compress this PDF catalogue so it is small enough to email as an attachment. Report the original and final sizes: https://example.com/catalogue.pdf
Tips
- State your size constraint clearly — ChatGPT can confirm whether the output meets it
- For heavily image-laden PDFs, expect the largest size reductions
- Ask ChatGPT to verify the compressed file URL is accessible before downloading