Reckon

You're handed six figures and an amount due. Settle the account exactly and earn the red SETTLED stamp.

Pick a figure, an operation (+ − × ÷), then a second figure — the result is pencilled in as a new figure you can spend. Each figure may be spent only once, subtraction must stay positive, and division must come out even: the ledger holds only positive whole numbers.

Once the account is closed, the auditor weighs in — if a shorter working exists, it's written up below yours.

One account a day. Everyone gets the same puzzle, derived from the date — no server, no answer list, and every account is guaranteed settleable. A fresh one opens at local midnight.

•  Streaks & stats — settle rate, best runs, and a distribution of how many lines your settlements take.
• Commendations — badges for settling in style: spend all six figures, use all four operations, settle with no undo, finish in three lines, or keep the streak alive.
• Past accounts — replay any previous day's puzzle for practice.
• Share result — a spoiler-free, paste-anywhere summary for group chats.
• Six stationery styles, from Counting house to Nightwatch (dark).

Also playable at https://jonezzyboy.github.io/reckon/ — source on GitHub.