How it works.
Money on TrezzerChest isn't real bills in a vault. It's a ledger: a running record of what your family's bank owes you. Real banks work the same way.
Two ways money arrives.
Someone put it there: allowance on its schedule, a birthday gift, cash handed over and recorded. Those show in ink.
It grew by itself: interest the bank paid for waiting. Those show in gold, marked . The gold parts are what your money earned by itself.
The power of compound interest.
Say the rate is 12% a year, compounded monthly: 1% each month. The growth itself grows, and every line of it is checkable on your own page.
We recommend a generous rate.
A real bank pays about 4%: too slow to see on a $10 balance, and seeing it is the point. Many families use 12%, then lower it as kids grow. Whatever you set, their page shows it plainly.
Every take-out is a trade.
Before any withdrawal, they see both futures first: what they'd have today, and what that money would have become if it stayed.
Take $20 today
You'd have $99.77.
Your savings goal for the bike moves Aug 4 → Aug 25.
Leave it
This $20 becomes ● $23 in a year…
…and ● $59 by eighteen.
Requests go to a person, not a machine.
Your request goes to your parent. When it's approved, the ledger writes it down and you get the cash in your hand.
Every line always adds up.
People write the facts: money in, money out, gifts, and changes to the rules. Your parent can log those for any day, or remove one logged by mistake. The bank writes the rest — allowance, interest, matches — and recomputes its own rows whenever the facts change, so the whole history is always exactly right.
What this costs and what it touches.
Free: no premium tier, no ads, no selling data. No bank connections, no cards, no real money. Kids sign in with a nickname you choose and a password you control; their pages carry no real-world identity and no analytics. Privacy →
Takes about two minutes. The first thing you'll do is set up your kid's page.
Already set up? Kid sign-in →