How swaps work
Mystery Swap is a group trade decided by chance. This page explains exactly what chance does and does not decide.
What happens, step by step
- You pick one item from your vault and the value band it falls in.
- Your item locks. It can't be traded, withdrawn or entered anywhere else while the group is filling.
- When the group is full, every item is shuffled and reassigned so nobody receives their own.
- All ownership transfers happen in a single database transaction. If any part of it fails, none of it happens and every item returns to its original owner.
- Your new item appears in your vault immediately, ready to trade, list or swap again.
How we keep values matched
Bands use the value our inspection team assigned when the item arrived — never a value the owner claimed.
Bands alone aren't enough, though. A $20–30 band would still let someone enter a $30 item and receive a $20 one, and that would be chance deciding whether they came out ahead. So a group only accepts an item if, afterwards, its lowest-valued item is still at least 85% of its highest. That check runs before any randomness does, so it holds for every possible outcome.
How the randomness works
Every random value is generated on our servers with a cryptographically secure generator. Nothing random runs in your browser.
Before a group opens, we generate a secret seed and publish its SHA-256 fingerprint. Because the fingerprint is published before anyone joins, we can't pick a seed that produces a result we prefer — we don't know who will be in the group yet.
After the swap runs, we publish the seed itself. Anyone can hash it, compare it to the fingerprint we committed to, re-run the shuffle and confirm the outcome matches. Every completed swap shows this proof on its own page.
Who can enter
- Identity-verified accounts only.
- 18 or older.
- Up to 5 swaps per day.
- Swaps are unavailable in some regions. If yours is one, the games page will say so.
- Accounts we've linked to each other are never placed in the same group.
If something goes wrong
If a group doesn't fill in time it's cancelled, every item unlocks and any entry fee is refunded in full. You can also pull your item out yourself any time before the group fills.
Every event in a swap — who joined, when the shuffle ran, what it produced — is recorded in an append-only log shown on the swap's page. That log is what we use to settle any dispute.
What Swapz does and doesn't do
Swaps are between players. Swapz never enters items, never plays against you, never contributes or removes items, and takes nothing based on what you receive. Entry costs the same regardless of outcome.
There are no rare items, no bonus tiers and no cash. Nothing can be added to a group beyond one item per player.
Questions about a specific swap? Open it from the games page — the full record is on every swap.