Help, Requests & Suggestions
Have a question about a calculator? Want a new one built? Spotted a bug or have an idea to make the site better? You're in the right place.
Created by
Daniel Whitman
Reviewed by
Hannah Brooks
Frequently asked questions
Are the calculators free to use?
Yes — every calculator on Calculator Friendly is free, with no sign-up required.
How accurate are your calculators?
We test each calculator against trusted reference formulas and worked examples before publication. That said, calculators are general tools — for important decisions, always confirm with a qualified professional. See our Disclaimer.
Do you store the values I enter?
No. Inputs are processed inside your browser and are not transmitted to our servers, unless a particular calculator clearly states otherwise.
How do you choose which calculators to build next?
Mostly from reader requests. The form below feeds directly into our backlog.