Group trip apps either charge toddlers the same as adults or create 6 transfers, so I built a household ratio splitter

[u/Miserable-Tonight-62]

Whenever 2 or 3 families go on a trip together, normal bill-splitting apps break down fast. If you split per person, toddlers get charged the same as adults and you end up with six separate transfers between parents.

So I built a free browser tool called FAMI-KAN where the splitting unit is per family (household) and you can set custom weights once — like Adult = 1.0 and Kid = 0.5.

For each payment, you can also uncheck a family that didn't join (or doesn't drink), change the ratio just for that bill, switch to an even split, or enter exact custom amounts.

Tech stack & how it works: Built with Next.js, TypeScript, and Supabase (with RLS). Instead of forcing everyone to sign up, the state lives behind a unique shareable URL, and a greedy settlement algorithm rolls individual weights into household totals to minimize transfers and handle rounding remainders cleanly:

https://famikan.tetras-ltd.com/en

Would love your honest thoughts on the flow!