babybumpkit is a small, independent project building free pregnancy calculators that are warm, accurate, and pleasant to use on a phone. We started it because most of the existing tools fall into one of two camps: clinical to the point of feeling cold, or so gimmicky and ad-stuffed they're unusable. There's room for something in between.
How the calculators are built
Each tool implements a standard medical formula and cites its sources on the page. Where guidance from major medical bodies (ACOG, Mayo Clinic, NHS, NIH MedlinePlus) exists, we follow it. Math runs in your browser — nothing you type is sent to our servers — and we never claim “100% accurate” results. Every page carries a visible medical disclaimer reminding readers that only an ultrasound and their healthcare provider can confirm a pregnancy timeline.
How content is edited
Our calculators, week-by-week guides and topic-section articles are written and edited by people, fact-checked against the medical guidance we cite. Last-updated dates reflect real edits, not cosmetic refreshes.
Blog articles are drafted with AI assistance against a fixed editorial brief, then checked automatically before they publish. That check requires every article to cite at least two sources, and it will only accept sources from a fixed list of ACOG, Mayo Clinic, NHS, NIH and CDC pages that we maintain by hand — so a citation here is never one an AI invented. It also rejects any article claiming a result is “100% accurate” or guaranteed, because every figure this site produces is an estimate. Anything that fails these checks is not published.
How the site is funded
At launch, babybumpkit carries no advertising and no analytics. Once the site is approved by Google AdSense, we plan to run a small number of display ads — never above the calculator, never in a way that interrupts the result. The site will remain free.
Get in touch
Spotted an error, have a tool you'd like to see, or want to contribute? Email hello@babybumpkit.com. We read everything.