FreeCryptoStore

Build a blockchain from scratch. Add transactions, mine blocks, tamper with data, watch the chain validate or break.

Type text and see SHA-256 update in real-time. Avalanche effect demo, bit visualization, mining challenge.

Build Merkle trees visually. Add leaves, watch hashes propagate, verify proofs, tamper with nodes.

Compare PoW, PoS, and PBFT consensus algorithms. Byzantine fault tolerance, message passing, fork resolution.

Generate mnemonics, derive keys via BIP-39/44, see the derivation tree, sign and verify messages.

Watch 5 miners race to find valid hashes. Adjustable difficulty, hashrate stats, block rewards.

Write and execute contracts in a simplified VM. Stack, memory, storage visualization. Gas tracking.

Constant-product market maker. Swap tokens, add liquidity, see price curves, impermanent loss calculator.

Watch transactions gossip through a network. Partition nodes, create forks, resolve with longest chain.

Design tokens with custom supply curves, bonding curves, inflation models. Simulate transfers and economics.

ECDSA step by step. Key generation, signing, verification. Visual elliptic curve operations.

Watch blockchains fork, compete, and resolve. 51% attack simulation, double-spend demo, orphan blocks.

Ali Baba cave ZKP demo. Play prover or verifier. Watch probability of cheating drop exponentially.

Stake in pools, watch rewards accumulate, compound vs simple interest, risk assessment, gas optimization.

Interactive block structure. Expand each field, compare Bitcoin vs Ethereum blocks, inspect the genesis block.

Interactive history from Diffie-Hellman (1976) to today. Key events, innovations, and their connections.

Simulate 51% attacks, Sybil attacks, eclipse attacks, and reentrancy exploits step by step.

Build a DAO: set voting rules, create proposals, vote with token-weighted governance.

Full decentralized exchange: create token, add liquidity, trade, watch price chart.

Optimistic vs ZK rollups side-by-side. Batching, fraud proofs, throughput comparison.

Draw pixel art, generate metadata, mint NFTs. Full ERC-721 flow simulated in browser.

Validators, epochs, slashing, delegation. See how PoS consensus works with rewards and penalties.

Step-by-step flash loan arbitrage. Borrow, trade between DEXs, repay — all in one atomic transaction.

EIP-1559 fee market. Blocks fill up, base fee adjusts, transactions compete. See why gas spikes happen.

Lock-and-mint, burn-and-unlock. See how bridges work and what happens when they get hacked.