splitseasOpen calculator 
SplitSeas is an independent, free shared-expense calculator maintained by Omar Fattahi. It helps friends work out group bills and trip costs without opening an account.
What stays simple
Add people and expenses, choose equal or weighted shares, then see the balances. Each expense can have several payers and its own currency. The calculator accounts for every minor unit and shows the reference rate used for conversions.
What it does not do
No stored ledger, bank connection, payment processing, subscriptions or advertising. Trips stay in your current tab. The ChatGPT integration processes one complete calculation at a time.
Check the details
Read the currency and rounding policy, privacy policy and terms. Use the worked examples to check the result. For help, reach 11digital.io@gmail.com.