Build a Churn Rate Calculator with Claude Code
Business analytics tool that calculates customer churn rates and retention metrics. SaaS companies and subscription businesses use it to measure customer retention and identify improvement opportunities.
The Claude Code prompt
Build a Churn Rate Calculator web app. People search for "churn rate calculator" about 450 times a month, plus related searches like "customer churn calculator", "retention rate calculator", "churn analysis tool". The goal is a tool that ranks for those searches and makes money. What it should do: Build a churn rate calculator with customer data input (start count, end count, new customers). Calculate monthly/annual churn rate, retention rate, and customer lifetime value. Include trend analysis, cohort tracking, and industry benchmarks. Add retention improvement suggestions and scenario planning. Focus on getting basic churn calculations working first. How to build it: 1. Read this folder first. If it is empty, set up Next.js (App Router, TypeScript, Tailwind). Write a short PLAN.md with the pages, components, any library or API you need, and what you are leaving for later. Then build. 2. Put the tool itself on the homepage so a visitor can use it within seconds, with no sign-up. Do the processing in the browser where you can, so it is fast and cheap to run. Look at how ChartMogul, Baremetrics, ProfitWell do it and make ours simpler and faster. 3. Make it rank. Use "churn rate calculator" in the title tag, H1 and meta description. Under the tool, add a short how-to and an FAQ with FAQPage schema, and add a sitemap and robots.txt. Scaffold these programmatic pages from one template and a data file: /churn-calculator-[industry], /retention-rate-[business-type], /customer-churn-[company-size]. 4. Monetisation: Freemium: Basic calculations, $15/mo premium + analytics. Add a pricing page and the free usage limit, and leave Stripe checkout as a clearly marked stub with the environment variables it needs. 5. Run it locally and test the main flow end to end, including edge cases like empty input and very large files. Fix what breaks, then finish with a summary of what works, what is stubbed and how to deploy it to Vercel.
Paste it into Claude Code in an empty folder. It plans first, so read PLAN.md and steer before it starts building.
What people search for
Who you're up against
- ChartMogul : Subscription analytics with churn tracking
- Baremetrics : SaaS metrics dashboard with churn analysis
- ProfitWell : Subscription metrics platform with retention tools
Pages that can rank
One template, many long-tail pages:
- /churn-calculator-[industry]
- /retention-rate-[business-type]
- /customer-churn-[company-size]
- /saas-metrics-[subscription-type]
Content to write
- How to Calculate and Reduce Customer Churn Rate
- Customer Retention Strategies for SaaS Companies
- Churn Rate Benchmarks by Industry
- Understanding Customer Lifecycle and Retention Metrics
How it makes money
Freemium: Basic calculations, $15/mo premium + analytics
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