Calculate cohort retention from user data

See what share of each signup month keeps coming back, as a cohort table and a short read-out.

You'll attach

Needs file

Works with

ChatGPTClaudeGeminiGrokCopilot

How to use it

1. Open chatgpt.com or claude.ai (or another AI listed here).
2. Attach the file (PDF, Word, CSV or Excel), or paste its text into the prompt.
3. Copy the prompt, paste it into the chat and send.

Using the attached data (columns for user ID, signup date and activity date), build a monthly cohort retention table.

- Rows: signup month. Columns: months since signup (0, 1, 2...).
- Cells: percent of that cohort active in that month.
- Explain how you defined "active".
- Then write 3 to 5 plain-language takeaways, like which cohort retained best and where the biggest drop happens.

If my columns are named differently, tell me which ones you used.