Fasting Center for Claude and ChatGPT

Last updated: Nov 12, 2026

Overview

The Fasting Center connector ("the connector") lets Claude and ChatGPT use the Fasting Center calculators. It is developed by Andrey Titov, an individual developer, alongside the Fasting Center app. Ask in plain language and get estimates from the same calculators that power the App.

Summary

  • No account or sign-in is needed.

  • The connector stores none of the numbers you give it.

  • It follows the same safety limits as the Fasting Center app.

  • Results are estimates, not medical advice.

What It Does

Extended fast calculator - estimated weight and fat loss for a water fast of 1 to 40 days, with a day-by-day curve. Longer fasts get a rough range.

Intermittent fasting calculator - where a daily calorie intake takes you over 1 to 52 weeks, or how long it takes to reach a goal weight.

Fasting stages - which stage of a fast you are in at any hour, in 17 languages.

Questions You Can Ask

  • I'm a 40-year-old man, 178 cm, 90 kg. How much would I lose on a 5-day water fast?

  • I'm 35, female, 165 cm, 75 kg. How long until I reach 68 kg on 1,600 calories a day?

  • What fasting stage am I in at 36 hours?

How to Add It

Claude: Open Customize, then Connectors. Find Fasting Center in the directory and connect it. In a new chat, make sure Fasting Center is turned on in the tools menu.

ChatGPT: Open Apps (or Plugins) and search for Fasting Center. Add it, then in a chat type @ and choose Fasting Center.

Custom setup: If you add connectors by address, use https://mcp.fasting.center with no authentication.

Safety Limits

The connector follows the same safety limits as the Fasting Center app.

  • No estimates for anyone under 18.

  • No projections below a healthy weight (BMI 18.5).

  • No projections below 800 calories a day.

  • Water fasts only - no dry fasting.

  • Fasts longer than 10 days come with a reminder to fast only under medical supervision.

Privacy

The connector needs no account and stores none of the numbers you give it. See the Fasting Center connector section of our Privacy Policy for details.

Health Disclaimer

The connector provides informational estimates about fasting. It is not a medical device and does not provide medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before starting a fast, especially if you have a medical condition, take medication, are pregnant or nursing, or have a history of disordered eating.

Contact

Questions or problems? Email us at support@fasting.center.