The problem: a group eats out, everyone ordered different things, someone paid, and now the group chat is doing bad math. Splitting equally punishes the person who only had water.
The solution: a single-page tool where you list each person's items, add tax/tip once, and it calculates exactly who owes what — with tax and tip distributed proportionally to what each person actually consumed.
Open index.html in any browser. Add people, add their items, set tax and tip, done. Works offline.
Vanilla HTML/CSS/JS, no dependencies, no build step. State lives in a single plain object; rendering is a small pure function. Proportional allocation avoids the classic rounding bug by assigning the leftover kobo/cents to the largest share.
- Add a "copy summary to clipboard" button formatted for group chats
- Support percentage-based OR fixed-amount tips
- Add a shareable URL that encodes the whole bill in the query string
Scaffolded by an automated weekly pipeline, then refined by hand — see the factory repo for how it works.