How It WorksLive ArenaFeaturesSecurityFAQLive BiddingRecent Biddings
Live on Stellar TestnetSoroban Smart Contracts

Sealed Bids.
Proven by Cryptography.

Commit a sealed hash, reveal after the window, and settle on-chain. No peeking — the winner is proven by cryptography, not trust.

Enter Real-time ArenaTestnet App Dashboard →
🛡 Non-custodial⛓ On-chain settlement🔒 Zero-knowledge commit
Charity Painting #42Commit Phase
Commit closes in
02:47:15
Highest Bid
●●●
Bidders
24
Commit Bid
tx: a4f3...8e1c
1,247+
Auctions Created
$2.4M+
Total Bid Volume
99.8%
On-chain Accuracy
<2s
Avg Tx Finality
THE PROTOCOL

Three phases. Zero leaks.

A cryptographically fair sealed-bid process built directly on Soroban.

Commit a Sealed Hash

Generate a secret salt. Hash your bid amount + salt together using SHA-256. Submit ONLY the hash on-chain. Your actual bid remains invisible to everyone — including the smart contract.

hash = SHA256(bid_amount || secret_salt)
submitHash(hash) → on-chain

Reveal Your Bid

After the commit window closes, reveal your original amount and secret. The contract verifies the hash matches. Invalid reveals are rejected. Front-runners can't peek — the window is already closed.

revealBid(amount, secret)
contract verifies SHA256(amount||secret)

Settle & Crown the Winner

Once the reveal window closes, anyone can trigger settlement. The contract finds the highest valid reveal and permanently records the winner on-chain. Fully transparent, fully verifiable.

settleAuction() → winner recorded on-chain
highest_bid: 450 XLM
WEBSOCKET PLAYGROUND

Real-Time Arena Lobby

Simulate commits, reveals, and settlements over WebSockets with other bidders. No testnet transaction approvals required.

⚡ Live Bidding Arena

No active simulated auctions. Connect wallet and click "+ Create Simulation Auction" to launch one!
Live Chat Lobby0 bidder(s) online
Waiting for bidders to connect...
RECENT ACTIVITY

Recent Biddings

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AuctionBidderAmountStatusTime

No bids recorded yet.

WHY SEALBID

Built for fairness. Designed for trust.

Traditional auctions leak bid information in real time, enabling sniping, front-running, and collusion. SealBid eliminates these attack vectors with commit-reveal cryptography baked into every auction.

Anti Front-Running

Bid hashes are submitted before amounts are known. No miner or observer can exploit your bid.

Soroban Native

Built on Stellar's Soroban smart contract platform. Fast finality, low fees, enterprise-grade security.

Freighter Wallet Integration

Connect your Freighter wallet in one click. Sign transactions securely without sharing your private key.

Cryptographic Proof

Winners are proven by on-chain hash verification. No centralized oracle or admin required.

Permissionless Creation

Anyone can create an auction. Set your own commit/reveal windows. No approval required.

Real-time Event Feed

Live blockchain event polling shows commit, reveal, and settle events as they happen.

SECURITY

Provable. Permissionless. Safe.

Commit-Reveal Scheme

The two-phase protocol ensures no bid is readable until after the commit window. Even the smart contract cannot see your amount during commit phase.

Hash Collision Resistance

SHA-256 with a 32-byte random salt makes brute-forcing your bid computationally infeasible. Your bid is safe even if an attacker knows your address.

On-chain Finality

Once settled, the result is permanently recorded on Stellar ledger. No admin, no rollback, no appeals — just cryptographic truth.

No Trusted Third Party

SealBid has no admin keys, no upgrade mechanism, and no off-chain oracle. The Soroban contract IS the authority.

Open Source & Auditable

All contract code is public on GitHub. Anyone can read, verify, and fork the auction logic.

FAQ

Common questions

In a sealed-bid auction, all bids are hidden from other participants until the bidding window closes. This prevents bidders from one-upping each other at the last second (sniping) and eliminates front-running. SealBid uses cryptographic hashes to enforce this on-chain.
You need the Freighter browser extension (Chrome/Firefox). Freighter is a non-custodial Stellar wallet that lets you sign Soroban transactions safely without exposing your private key.
1) During the Commit phase: enter your bid amount, generate a random secret, and submit the SHA-256 hash of amount+secret on-chain. 2) During the Reveal phase: submit your original amount and secret — the contract verifies the hash matches. 3) After the reveal window: call settle() to record the winner.
If you miss the reveal window, your commit is ignored. The winner is determined only from valid reveals (where hash verification passes). Always save your secret somewhere safe!
This is currently a testnet deployment for demonstration purposes. Contracts are open source and publicly verifiable on Stellar Expert. Always exercise caution on mainnet deployments.
Stellar transaction fees are among the lowest in Web3 — typically 0.00001 XLM per operation. Creating, committing, revealing, and settling each cost a fraction of a cent.