Habit Formation Calculator
How far along you are toward making a habit automatic.
Your result
Research found habits took 66 days on average to become automatic, with a range of 18 to 254 days. The curve shown is an illustration, and missing a day rarely matters.
Medical disclaimer: This tool is for education and is not medical advice. Read more.
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Frequently asked questions
What does the Habit Formation Calculator do?
How far along you are toward making a habit automatic. Enter your values and the result and chart update instantly.
How accurate is it?
It uses published, widely used formulas. Results are estimates for education and planning, not a diagnosis. Talk to a qualified clinician about decisions affecting your health.
Is my information stored or shared?
No. All calculations run in your browser and nothing you type is sent to a server or saved.
What can I search to find this tool?
People find it by searching for: how long to build a habit; habit tracker; new routine progress.