Swap testnet coins
An atomic swap trades one coin for another across two different blockchains with no custodian. It either completes fully or safely refunds both sides. TestnetSwap does tLTC ↔ tBTC, plus experimental tXMR/sXMR → tBTC swaps.
What is an atomic swap?
Normally, trading one coin for another means trusting an exchange to hold your funds. An atomic swap removes the middleman: two people trade directly across chains, and cryptography guarantees the trade is all-or-nothing. Either both sides get paid, or both get their original coins back. Nobody ever holds your coins.
How it works (HTLC)
For Bitcoin and Litecoin, the trick is a hash time-locked contract (HTLC): coins are locked behind a secret, with a refund deadline if the swap stalls.
The four phases
Setup
You and the maker agree on the pair, amount, and two refund deadlines, over a relay that only passes messages and holds no keys or coins.
You lock
Your wallet locks your coins in a contract on the chain you're sending from. Only you can refund it, and only after your deadline.
They lock
The maker sees your funded contract and locks the other coin on the receiving chain, behind the same secret, with a shorter deadline.
You claim
You claim the maker's coins by revealing the secret. That same secret lets the maker claim yours. The swap completes atomically.
The worst case is safe
If anything stalls, you reclaim exactly what you locked (minus network fees) after your deadline. A maker can never take your coins, because they can't claim yours without revealing the secret that lets you claim theirs.
Monero swaps are different
Monero can't use the same HTLC scripts, so tXMR/sXMR → tBTC swaps use a cross-chain adaptor-signature protocol instead. The non-custodial, all-or-nothing guarantee is the same, but this path is still experimental and in active development, so expect it to be slower and less polished than tLTC↔tBTC. See the Monero guide for why Monero behaves differently.
Try it
- Get both testnet coins from the faucet.
- Open TestnetSwap.
- Pick the pair and amount.
- Your wallet locks, the maker locks, and you claim. Done. Watch each step confirm on the explorer.
Also built into your wallet
The same swap is available natively inside TestnetWallet, so you can trade coins without leaving the wallet. It runs the identical non-custodial swap under the hood.
Testnet coins are fake money
- They have no market value, so never buy or sell them.
- Never use a real seed phrase or import a real wallet on testnet.
- Never send mainnet BTC, LTC, or XMR to a testnet address.