What to write about
Corrections
This is the one we most want to hear. If a formula is wrong, a range is out of date, or a page states something that the current evidence does not support, tell us — errors in health content matter more than most. Please include the page and, if you have one, a source. Corrections are made on the page itself.
Calculator requests
If there is a calculation you keep doing by hand, say so. Requests genuinely shape what gets built next.
Accessibility problems
If a calculator does not work with your screen reader, keyboard or browser, that is a bug and we would like to fix it. Please mention which page and which assistive technology you use.
Advertising and partnerships
Advertising enquiries are welcome. Note that advertisers have no say in what the pages say, and we do not publish sponsored content dressed up as editorial. Any commercial arrangement that ever affects a page will be disclosed on that page.
What we cannot help with
We cannot answer personal medical questions. Not because we would rather not, but because nobody can do it responsibly by email without your history, your medications and an examination. If you have a health question about yourself, please take it to a GP, pharmacist or registered dietitian — they can help in ways a website cannot.
If you are struggling with food, eating or your relationship with your body, a doctor is the right first step, and it is a far more common conversation than most people expect. In Australia, the Butterfly Foundation National Helpline is on 1800 33 4673. In the UK, Beat is on 0808 801 0677. In the US, the National Alliance for Eating Disorders helpline is on 1-866-662-1235.
If you are in immediate danger or crisis, please contact your local emergency number — 000 in Australia, 999 in the UK, 911 in the US.
Privacy
Emails you send are stored in our mailbox and used only to answer you. They are not added to any list and not shared. See the privacy policy for how the rest of the site handles data — the short version is that your calculator inputs never leave your browser.