Straight answers, no fluff. If something here doesn't cover your case, our humans are one click away.
Middn is a privacy-first, AI-assisted P2P trading layer built on smart contracts. Two people who don't know each other can trade tokens, NFTs, or any on-chain asset, and the contract handles the escrow + settlement atomically.
Think of it as the missing trust layer between a CEX and a raw on-chain transfer. No custody, no KYC, no middleman taking your funds for "review."
Four steps:
See how it works for the full walkthrough with illustrations.
Anyone who wants to trade directly with another person, on-chain, without trusting a custodial middleman:
Currently live on Ethereum mainnet, Base, Arbitrum, Optimism, Polygon, and Solana. We're adding Avalanche and Sui in Q3 2026.
Cross-chain swaps go through a 2-step escrow with HTLC-style locks — no centralized bridge needed.
Yes. Audited by Trail of Bits (March 2026) and Halborn (April 2026) — zero critical findings on both. A $250k bug bounty is live on Code4rena.
Every report is public, every line of code is open-source. See audits for the full reports.
No. Middn is non-custodial — your funds go directly from your wallet into a smart contract you can verify on-chain. We don't hold any keys. We can't move your assets even if we wanted to.
If our entire infrastructure was compromised tomorrow, your funds would still be safe in the contract. The only thing an attacker could do is take down our front-end, and you'd still be able to interact with the contracts directly via Etherscan.
Every deal has a timeout. If the counterparty hasn't locked their funds (or fulfilled their condition) by the deadline, you can call refund() and get your assets back instantly. No support ticket, no waiting.
The timeout is set by you when designing the deal — usually 1h to 48h depending on the asset.
We can't. This is the trade-off with non-custodial systems — if you lose your keys, we have no way to recover your funds. Nobody does.
Use a hardware wallet. Back up your seed phrase. Store it offline, in multiple places.
Three things, all advisory — never custodial:
The AI never moves your funds. It can't. Only the contract can.
Only what you explicitly share with it. The AI runs client-side first for risk checks (on the encrypted blob you'd send). For deeper dispute help, you can opt-in to send a redacted summary to our server-side model, but it's never automatic.
And no, we don't train on your data. The model is a fine-tuned open-source LLM with retrieval over public on-chain history.
It doesn't resolve — it summarizes. The AI generates a neutral case file from on-chain events, ZK proofs, and any evidence both parties submit. That summary then goes to a small panel of opt-in human arbitrators (Kleros-style) who vote.
The contract enforces whatever they decide. We don't have a "support team" that overrides decisions.
Yes — privacy is the default, not an opt-in. Every message between you and your counterparty is encrypted end-to-end (AES-256 + X25519). The conditions of your trade are verified by ZK proofs, so the chain never sees the underlying data.
What's public? Only the bare minimum: a commitment hash, the asset addresses, and the final settlement. Amounts and conditions stay encrypted unless you choose to disclose them.
No. Middn is a permissionless protocol — there's no signup, no email, no ID. Just connect your wallet and trade.
Some integrators may require KYC for fiat on/off-ramps depending on your jurisdiction, but that's their flow, not ours.
From our front-end: nothing personal. We use privacy-respecting analytics (Plausible — no cookies, no IP logging). No fingerprinting. No tracking pixels.
You can run the front-end locally or via IPFS if you want zero contact with our servers. Same contracts, same experience.
A flat 0.15% protocol fee on the trade value, split between both parties (so 0.075% each). No subscription, no monthly minimum, no hidden fees.
For trades over $100k, the fee drops to 0.08%. For under $50, it's free.
Plus standard chain gas — usually a few cents on L2s, more on Ethereum mainnet.
By default, each party pays the gas for their own actions (locking, claiming). For the atomic settlement, one party pays — usually the one initiating — and the other can choose to refund a portion off-chain.
We're rolling out gasless flows (EIP-2771 meta-tx) for L2 deals in Q3 2026.
Not at launch. We may introduce one later for governance — community voting on fee parameters, supported chains, treasury — but it would never be required to use the protocol.
We're not interested in "use our token to get a discount" extraction patterns.
First, check the explorer. If your tx is in mempool but not confirmed, it's usually a gas issue — try speeding it up or canceling from your wallet.
If the on-chain tx is confirmed but Middn shows "pending," refresh the page. Our UI fetches from the chain directly; there's nothing to "process" on our side.
If it's still wrong after 5min, ping us on Discord with the tx hash.
If the funds went to the Middn contract via the proper flow — they're recoverable: just call refund() after the timeout, or get your counterparty to settle correctly.
If you sent funds directly to a random address bypassing the protocol — there's nothing we can do. We can't recover funds sent outside of our flow.
Don't sign anything yet. The AI agent will usually flag suspicious patterns automatically — bad reputation wallets, unrealistic prices, urgency pressure tactics. Pay attention to those warnings.
If you're unsure, paste the deal link in our Discord #help channel. Other users + the team will sanity-check it for you in minutes.
You can always cancel before signing — nothing is committed until your wallet broadcasts.
Try these in order:
Still broken? Hop in Discord with your browser + wallet version. We respond fast.
If the FAQ didn't cover it, our team and community are happy to help. We answer fast.
For private issues, anything sensitive, or just longer questions. PGP key available.
[email protected]The whitepaper has everything technical — circuits, contracts, threat model, the works.
Read the docs →Most questions disappear once you've done one trade. Takes 30 seconds.