How to calculate age?

Please check and test my demo form: https://form.jotform.com/82424733028959

Is that what you're trying to create? If yes, here's a guide on how to calculate age using Calculate field condition, Number field, and two Date Picker field:

1. First, add two Date Picker field. Please set the one Date Picker field to Current Date.

2. Add the Number field.

3. Use the Calculate field condition to calculate the age and pass it to the Number field. Here's a guide: How-to-Insert-Text-or-Calculation-into-a-Field-Using-Conditional-Logic

Here's the formula to calculate age:

 

You can also hide the Current Date in the form so the user will only see the Birthday field. You can also clone my demo form to check the condition further. Here's a guide: https://www.jotform.com/help/42-How-to-Clone-an-Existing-Form-from-a-URL

Please give it a try and let us know how it goes. Thank you.

Excellent instructions and step-by-step guide. Thank you so much
Mark
LRMC
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I can’t figure out how to remove the decimal in the age field.
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Sorry, but I'm not able to find the "Age" field in this form https://www.jotform.com/81963636366165 that has a decimal. Would you mind sharing to us the form URL for us to check?

Looking forward for your response. 

https://form.jotform.com/82336614266155 I age field that has a decimal is under MINOR Child/Legal Guardin,
Thanks
Mark
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Hi Mark,

After editing the calculation expression on your form, the decimal is not being shown anymore.

Result:

Let us know if you need further assistance.