Frequently Asked Questions

A real-time blockchain visualizer. Instead of cryptographic hashes, you watch live transactions flow through Bitcoin, Ethereum, and Base as animated "buses" picking up "passengers." 65% of people learn best visually—this makes blockchain mechanics immediately clear. Learn more about our approach.

Zero setup. Visit the homepage—no wallet, no login, no installation. Use the dropdown (top right) to switch between Bitcoin, Ethereum, and Base. The visualization updates in real-time as blocks confirm. Green dots (pending transactions) get picked up by animated buses (confirmed blocks) as consensus happens globally.

Yes. Free, no paywalls, no premium tiers. Supported by non-intrusive advertising that covers infrastructure costs.

No. This is a pure observation tool—like a traffic camera for blockchains. You're not submitting transactions or risking funds. We never ask for wallet addresses or private keys. You can't lose money here.

Pending transactions waiting in the mempool—a queue where transactions compete for inclusion in the next block. During peak activity you'll see hundreds as users submit swaps, transfers, mints, and contract interactions. Dot counts match real-time mempool data from blockchain nodes.

A confirmed block. Just as a city bus picks up passengers, a block collects pending transactions and confirms them on the ledger. Each bus shows its block number and transaction count. Colors indicate dominant transaction types—green for transfers, blue for swaps, purple for mints. Bus frequency shows network speed: Base every 200ms, Ethereum every 12 seconds, Bitcoin every ~10 minutes.

Layer 2 blob transactions. Blue = Base, red = Optimism, gray = Arbitrum, black = World Chain. Each bundles thousands of L2 operations into a single Ethereum transaction—one blob might represent 10,000 transfers. In 2025, L2 solutions handled 63% of Ethereum volume.

Left zone: pending transactions in the mempool, waiting for block inclusion. Right zone: confirmed transactions, successfully on-chain. Watching transactions move left to right shows the full lifecycle: submission, waiting, inclusion, confirmation. "Transaction finality" becomes tangible.

Design tradeoffs. Bitcoin targets ~10-minute blocks for maximum security via Proof-of-Work. Ethereum uses Proof-of-Stake with 12-second slots. Base achieves 200ms blocks (via Flashblocks) by processing off-chain and settling to Ethereum. The visualization reflects these real differences—Base buses arrive constantly, Ethereum moderately, Bitcoin sporadically but with more transactions per block.

A cryptographically signed instruction to change the blockchain's state. For Bitcoin: transferring BTC between addresses. For Ethereum: sending ETH, trading on Uniswap ($50B+ monthly volume), minting NFTs, providing DeFi liquidity, or running arbitrary smart contract logic. Each transaction is signed with a private key, broadcast to nodes, validated, and permanently recorded.

A waiting area for unconfirmed transactions on each node. Your transaction joins thousands of others. Miners or validators pick transactions for the next block, prioritizing higher fees. When demand exceeds block space, the mempool swells and fees rise. In the visualization, this is the bus stop where green dots accumulate—more dots means more congestion.

Gas measures computational effort. Simple transfers: ~21,000 gas units. Complex contract calls: 200,000+. You set a gas price per unit; total fee = gas used × price. During congestion, users bid competitively for limited block space, spiking prices. In 2025, average fees fell to $0.38 as L2 adoption absorbed volume. The "median transfer fee" stat shows typical costs for recent blocks.

L1 (Bitcoin, Ethereum): base protocols where every node validates every transaction. L2: scaling solutions on top. L2s process transactions off-chain, then commit compressed batches to L1 for security. This cuts per-transaction costs dramatically—Arbitrum costs ~$0.005, Base and Optimism are similar—while inheriting Ethereum's security. The visualizer shows both L1 blocks and L2 blob submissions.

(1) Submit a signed transaction to a node. (2) The node validates and broadcasts it to peers—it enters the mempool. (3) Miners/validators select it for the next block based on fee priority. (4) Included in a block = first confirmation. (5) Each subsequent block increases irreversibility. Bitcoin typically requires 6 confirmations (~60 minutes); Ethereum finalizes in 12-15 minutes; Base offers near-instant finality via optimistic rollups.

Sending cryptocurrency from one address to another—the most basic blockchain operation. On Ethereum, this usually means ERC-20 tokens (USDC, USDT, DAI). Native ETH transfers appear separately. Covers peer-to-peer payments, exchange deposits, protocol rewards, treasury movements. Like wire transfers, but censorship-resistant, borderless, and settled in minutes.

Exchanging one cryptocurrency for another on decentralized exchanges (DEXs) like Uniswap, SushiSwap, or Curve. Unlike centralized exchanges, DEX swaps happen on-chain through automated market makers (AMMs)—you trade against liquidity pools with algorithmically determined prices. Uniswap handles $50B+ monthly volume with 55% DEX market share. Swaps often dominate Ethereum blocks during heavy DeFi activity.

Creating new tokens or NFTs. An artist minting artwork on OpenSea, a user minting DAI by depositing collateral into MakerDAO, a protocol distributing governance tokens. Unlike transfers (moving existing tokens), mints increase total supply according to smart contract rules. Especially visible during NFT launches when thousands mint simultaneously.

Transactions we can't classify by method signature: custom contract functions, flash loans, governance votes, staking, cross-chain bridges, novel DeFi strategies. Ethereum's programmability means developers constantly create new transaction types. Today's "other" becomes tomorrow's category.

Directly from production networks via Alchemy's RPC infrastructure—the same used by OpenSea, dYdX, and Axie Infinity. Every data point streams from blockchain nodes in real-time. Polling matches block cadence: every 200ms for Base (post-Flashblocks), 12 seconds for Ethereum, 30 seconds for Bitcoin. No simulations, no cache. More on our architecture.

Whenever a block confirms—real-time, not snapshots. Base: ~200ms (5 blocks/second). Ethereum: every 12 seconds. Bitcoin: roughly every 10 minutes, though Proof-of-Work variance means sometimes 5, sometimes 15. WebSocket connections push block data to your browser with minimal latency.

The numbers are exact—straight from the blockchain. For large blocks (200+ transactions), the animation uses proportional sampling to keep things smooth and readable. The visual "feel" of block size is preserved; the counts are always 100% accurate.

Node.js backend with viem for blockchain RPC. WebSockets for real-time delivery. Vanilla JavaScript and HTML5 Canvas for hardware-accelerated animations—no heavy frameworks. Result: sub-2-second loads, smooth performance on older devices, broad browser compatibility.

Real-time only. "Recent Blocks" shows the last 10 confirmed blocks. For history, use Etherscan (Ethereum), BaseScan (Base), or Mempool.space (Bitcoin).

Check your internet connection, then refresh (Cmd+R / Ctrl+R). If watching Bitcoin, blocks only arrive every ~10 minutes—this is normal. Check the "Latest Block" number to verify data flow. Try switching chains to isolate the issue. The backend auto-reconnects within 5 seconds.

Close other tabs and apps to free CPU/memory. Older devices may struggle with 200+ transaction blocks on Ethereum or Base. Switching to Bitcoin (fewer transactions, slower blocks) helps on constrained hardware. Use a current version of Chrome, Firefox, or Safari for best Canvas performance.

Yes. Fully responsive, optimized for mobile GPUs. Works on iPhone, iPad, and Android. Larger screens show more detail—desktop is best for classroom use or deep exploration. Mobile is fine for casual viewing.

Usually temporary connectivity issues. The visualizer auto-reconnects every 5 seconds. If errors persist, refresh the page. Switch chains to check if the problem is network-specific. Errors across all networks suggest brief infrastructure maintenance—check back shortly.

Google Analytics collects anonymized stats: page views, session duration, country-level location, device type, browser. We do NOT collect names, emails, wallet addresses, transaction data, or browsing history. Blockchain data streams from public networks to your browser—never stored on our servers.

Google Analytics sets first-party cookies for basic metrics (session length, navigation, return visits). Disable with uBlock Origin, Privacy Badger, "Do Not Track," or incognito mode. AdSense may set ad cookies. No third-party tracking pixels, no social media trackers, no data sales.

Completely safe. Read-only—we can't initiate transactions, access wallets, or interact with smart contracts. You're watching public data, like checking weather.com. No funds at risk, no private keys exposed. HTTPS encrypted. Zero risk.

Yes. Visual techniques improve test scores by 30% and 81% of students feel more motivated with visual elements. Use it in lectures, syllabi, homework, or demos. No attribution required.

Yes. No inappropriate content. Middle schoolers (11-13) grasp the bus metaphor; high schoolers can explore gas fees, L2 scaling, and consensus. Good starting point for discussions about digital currencies, fintech, and cryptography—analogies instead of intimidating specs.

No embed widget yet—it's on the roadmap. Link freely from websites, blogs, or LMS platforms (Canvas, Blackboard, Moodle). Deep links work: blocko.fun/?blockchain=bitcoin, blocko.fun/?blockchain=ethereum, blocko.fun/?blockchain=base.

Next steps: (1) Explore Etherscan or Mempool.space for raw transaction data. (2) Read the Bitcoin and Ethereum whitepapers. (3) Take courses on Coursera, Udemy, or MIT OpenCourseWare. (4) Join Reddit (r/CryptoCurrency, r/Ethereum) or Discord communities. (5) Try testnet transactions on Sepolia to experience blockchain firsthand with fake money.

Performance. A Base block with 500 transactions means 500 dots updating 60 times per second—that strains even powerful hardware. Proportional sampling preserves the visual feel of block size while keeping animations smooth. Transaction counts are always exact; the dot rendering is optimized.

The "Median Transfer Fee" stat shows typical recent costs. For detailed gas tracking and fee estimation, use Etherscan's Gas Tracker, Blocknative, or L2Fees.info for Layer 2 comparisons.

Evaluating candidates: Solana (ultra-high throughput), Polygon (Ethereum sidechain), Avalanche (subnet architecture). Priority is data quality and meaningful visualizations over quantity. Let us know which chains you'd find useful.

Not here—this is an observation tool, not a monitoring platform. For alerts, use Etherscan's app, Blocknative, or wallet notifications in MetaMask/Rainbow.