How Change Jar works end to end, with the details a careful person would want before using it.
Link a card. A standard open-banking connection shares two fields per transaction: merchant and amount. Balances, other accounts, and line items are never shared.
Every purchase rounds up. Each purchase rounds to the next dollar. The difference is tagged to the merchant and held in your jar until the weekly sweep.
Merchants map to stocks. Merchants map to stock tokens through a public, editable table. Starbucks to SBUX, Target to TGT. Merchants without a listed stock map to the market.
Once a week, the jar buys. Each merchant's change buys that merchant's stock token at market on Robinhood Chain. A flat five-cent fee applies per sweep. Muted merchants are swept into the market fund instead.
| Data | Kept |
|---|---|
| Merchant and amount per transaction | 90 days |
| Balances, other accounts, line items | Never received |
| Wallet address | Until account deletion |
| Sweep history | Public on chain |