Ethereum Blog

A TRON swap can need tens of thousands of Energy units, and a complex contract call can need much more. Energy is TRON’s measure of the computing work a smart contract performs; it is separate from Bandwidth, which covers transaction data. Knowing which resource is short helps explain why a swap may cost TRX or fail. Why can a swap need more Energy than expected? A token swap runs through smart contracts, which are programs that update balances and carry out trades. Each step uses Energy, so a route involving several contracts may need more than a simple token transfer. The exact amount depends on the contracts, the route, and the state of your wallet. A less obvious factor is the receiving token account’s history. A contract may need extra work the first time it writes a balance for an address. So two otherwise similar swaps can use different amounts of Energy, even when they trade the same token. For a TRON swap, check the wallet’s transaction estimate before approving. The estimate ...

Slashing can punish provable misconduct, but it cannot return XMR already stolen. Multisignature custody spreads control across key holders; slashing only costs their posted bond after a rule breach is detected. To wrap XMR into zXMR, use the ZeroFi XMR bridge to start the transfer, then check what the bond can actually cover. What does slashing deter? Slashing deters actions that a bridge can prove and punish. It means taking some or all of a node operator’s posted stake after a rule breach, such as signing two conflicting messages. It does not automatically stop a key holder from joining a group theft. Nor does it guarantee repayment: the bond may be smaller than the stolen XMR, or the bridge may lack clear evidence to trigger a penalty. For example, if a bridge holds 100 XMR and the operators’ total slashable bond is worth 5 XMR, a successful theft could still leave users short. Those figures are illustrative, not ZeroFi terms. Slashing changes the cost of misconduct; it is not de...

If you are used to withdrawing from an exchange, a self-custody bridge transfer usually takes minutes into Polygon PoS and longer on the way back to Ethereum. The difference comes from the work each network must confirm, so “sent” does not always mean “ready to use.” Why does direction change the timing? Ethereum-to-Polygon deposits commonly take around 10–30 minutes, while Polygon-to-Ethereum withdrawals often take about 45 minutes to three hours. These are illustrative ranges, not promises: congestion, confirmation delays, and bridge processing can stretch them. Think of a bridge like a parcel service that must check the sender’s handoff and then get the receiving depot to accept it. A centralised exchange may hide those checks behind one status label; with your own wallet, you can see separate transactions and stages. What happens during a deposit? For an Ethereum-to-Polygon deposit, you authorize a transaction on Ethereum that locks the ERC-20 token in the bridge’s Ethereum contrac...

If you are preparing your first cross-chain transfer, estimate the source transaction, message delivery and any destination action before deciding how much to send. The full cost depends on what the application must do on both networks, not simply on the amount transferred. Add source-chain gas, cross-chain delivery charges and any token or swap fee. Destination execution is priced into some message quotes; a later transaction may still need separate gas. Compare the same route and action using a fresh quote, then leave room for fee changes. Count each cost along the route Start with the source transaction: the network’s gas charge for submitting your transfer or message. If the token needs an approval transaction first, include that too; gas is usually paid in the source network’s native token, even when the asset you send is different. Next, add the cross-chain message or bridge fee. It can cover message verification and delivery, plus an estimate of the gas needed to run an instruc...

Give each cross-chain application flow its own message channel when it needs independent delivery state or ordering; combine flows only when they truly need to advance together. In practice, a channel keeps track of which messages belong to which sender, destination and receiver, so one application’s sequence does not automatically become another’s. A channel separates message tracking; it does not reserve blockchain capacity. Ordered delivery can make one failed message hold up later messages in that channel. Separate receiver contracts can provide separate message sequences for distinct flows. What does a message channel isolate? A message channel is a protocol’s record of traffic along a particular application path between chains. For example, LayerZero V2 tracks message nonces—the sequence numbers assigned to messages—by sender, destination chain and receiving contract. It also records verified payload hashes so the protocol can check a message before delivery and prevent it from ...

If your withdrawal returns several tokens but your next payment accepts one, compare the cost of swapping them into that token before you move the funds. Blackhole swap is an Avalanche C-Chain option when its pools support the assets and target you need; a direct swap on another suitable venue or keeping the assets separate may suit you better if either reduces cost or matches what you can spend. Before signing, use how to check Blackhole swap approvals for the step-by-step approval detail. Choose a target you can spend Pick the final token based on the recipient or checkout requirement, not simply the largest balance in your wallet. A stablecoin can make the amount easier to budget, while AVAX may be the useful target if you need the network’s native token; keep some AVAX aside for transaction gas either way. A pool withdrawal returns its underlying assets according to the pool’s reserves and, for concentrated liquidity, the position’s range and current price. If you withdraw two vo...

If you have bridged tokens in your wallet, first check the pool’s exact token pair, then swap only what you need to match it. For example, a pool needing ETH and USDC may require you to trade some bridged USDC for ETH on Base before adding liquidity. Keep extra funds for network costs. Check what the pool needs before swapping A liquidity pool is a shared pot of two tokens that people can trade between. To add liquidity, you usually need both tokens in the pair; having the right ticker alone is not enough. A bridged token is a version moved from another network, and its name may look like the original while its issuer or contract differs. Imagine you bridged 200 USDC to Base, Coinbase’s network built on Ethereum, and want to join an ETH–USDC pool. Check that your wallet holds the intended USDC on Base and identify the pool’s ETH token. Pool proportions can change with prices, so the required amounts may not be equal in dollars. Convert only the amount needed, then add liquidity Use th...

TRON energy and available bandwidth are separate balances because they pay for different parts of a transaction. Bandwidth covers the bytes recorded on-chain; Energy covers the smart contract work performed by the TRON Virtual Machine (TVM). A USDT transfer can use both, so having plenty of one does not guarantee that the other is available. The two balances measure different work Energy measures computation, while Bandwidth measures transaction size. A contract call uses Energy as the TVM executes instructions; its transaction data and result use Bandwidth according to their on-chain byte size. Neither balance is a general-purpose fee credit that can cover the other. Energy: consumed when a smart contract runs. Bandwidth: consumed according to the size of a transaction stored on-chain. TRX: burned to pay for a resource shortfall after applicable resources are used. Free Bandwidth: an account quota that can cover some transaction bytes; Energy has no equivalent free quota. A USDT T...

Cancel an NFT listing by sending a cancellation transaction from the wallet that controls it, using the marketplace where you listed it. A listing’s expiry time may stop buyers from accepting it, but it may not remove the listing or return an NFT held by a contract. Check what your marketplace does before you act. What happens when I cancel a listing? Canceling asks the marketplace’s smart contract—a program that runs on the blockchain—to invalidate your offer. Depending on how that marketplace works, the NFT may stay in your wallet or be returned to it from contract custody. Expiry and cancellation can be different. Expiry may prevent a sale after a set time, while a separate transaction is needed to clear the listing or release an escrowed NFT. “Escrow” means an asset is held by a contract until a rule is met. For example, if you listed an NFT last week and now want to keep it, check whether the marketplace says the listing is active and whether the NFT is still in your wallet. If i...

The recipient’s USDT balance can change the Energy a transfer uses. A transfer to an address with no USDT balance often needs about 130,000 Energy, while one to an address with a balance often needs about 64,000. These are examples, because the amount can change over time. Why does the recipient’s balance change the cost? USDT on TRON uses a token standard called TRC-20. When you send it, the token’s smart contract—a program that updates balances—runs on the TRON Virtual Machine (TVM), the network’s program engine. The contract must write the new balance into its records. If the recipient’s balance is zero, that write costs more than changing a balance that is already above zero. This storage write is one reason TRON energy use can differ between two transfers. “First transfer” can be misleading: the deciding factor is the balance when the transaction runs. If someone once received USDT but later spent all of it, their balance is zero again, so your transfer may need more Energy. What...

Slippage is the difference between a token’s quoted price and the price you get when a swap completes. For frequent BNB Smart Chain trades, the key factor is your order size compared with the available liquidity, or tokens ready to trade at nearby prices. Check both before swapping: low network fees cannot fix a thin pool. Price impact starts with pool depth Price impact is the price change your own trade causes inside a liquidity pool. A liquidity pool is a shared pot of two tokens that traders swap against; larger orders use up more of the token available at the current price. For a simple example, imagine a pool holding $100,000 of Token A and $100,000 of Token B. A $1,000 buy of Token A would move the price by roughly 2% in a basic constant-product pool, before the trading fee. That pool rule adjusts the exchange rate as one token is removed and the other is added. Now compare a $100 buy in the same pool: its price impact would be much smaller. Splitting the $1,000 into ten swaps ...

A split route can improve a large swap’s output when pools have uneven depth. A router divides the input among separate liquidity pools, then combines their output in one transaction; the improvement only helps if it exceeds the extra fees and network cost. What Does a Split Route Change? A split route sends portions of one token input through separate paths at the same time. That differs from a multi-hop route, which sends tokens through one pool and then another—for example, USDC to WAVAX to a third token. A router may combine both approaches. Each pool sets its price from its available liquidity and trading formula. In a constant-product pool, a trade changes the token balance ratio, so a larger order moves the price more. Avalanche Support describes this pool-based pricing; Uniswap’s developer documentation explains how a router can compare paths through multiple pools. For an Avalanche trade such as Blackhole swap, the useful question is whether splitting improves the amount you r...

If your crypto is in a self-custody wallet but an NFT marketplace runs on another chain, bridge the marketplace’s accepted payment token to that chain, then connect your wallet there. A bridge moves fungible assets such as USDC; it does not move your NFT or make a marketplace listing available on every network. Check the marketplace’s chain and accepted payment token before bridging. Bridge only enough to cover the purchase and fees, and keep native gas money for transactions. Confirm the destination balance in your wallet before buying. What do you need to check before moving funds? Find the exact network required by the collection or listing, then check which tokens the marketplace accepts on that network. The same marketplace may show NFTs from several chains, but each NFT belongs to a particular chain; Ethereum’s ERC-721 standard identifies a token by its contract address and token ID. As the Ethereum documentation explains, that on-chain identity is what distinguishes one NFT from...

To set slippage on a Syncswap swap, choose the smallest tolerance that leaves room for the quoted price to move before your transaction executes. Syncswap is a decentralized exchange and liquidity hub on zkSync Era, where a Smart Router can move a trade through one or more pools. The setting matters because the price shown when you prepare a swap is not necessarily the price used when the transaction is confirmed. The main trade-off is straightforward: a tight limit protects your price but increases the chance that the transaction reverts; a wide limit makes execution more likely but gives the market more room to deliver less than expected. Choose between protection and execution A low tolerance suits a liquid pair, a normal market, and a trade that is not urgent. If the quote is for 1.0000 units of the output token and the tolerance is 0.10%, the transaction should require at least 0.9990 units. A move beyond that threshold causes the swap to fail instead of accepting the worse price...

Atomic swaps exchange assets directly by locking each side of a trade to the same cryptographic secret and releasing both sides only when the redemption condition is met. The working model is 2 ledgers, 2 contracts, 1 secret, 1 hash, and 2 refund deadlines . That small set of parts explains both the appeal and the limits: neither asset needs to leave its native network, but both networks must support compatible settlement rules. How the swap settles In the classic design, the two parties use hash time-locked contracts, or HTLCs. One contract says, “Release the asset to whoever can present the secret whose hash equals this value before the deadline.” The time lock adds a second condition: if nobody presents the secret in time, the original owner can reclaim the funds. Alice generates a random secret and publishes only its hash. Alice locks bitcoin on Bitcoin using that hash and a later refund deadline. Bob sees the hash and locks litecoin on Litecoin with the same redemption condition ...

Token burns reduce supply only when the burned balance is actually removed from the token’s accounting; in a bridge, a burn may simply retire one representation before an equivalent amount is minted elsewhere. This is the point that causes confusion on a first cross-chain transfer. The source transaction succeeds, an explorer shows a Burn event, and tokens appear in the destination wallet. It looks as though supply fell. Sometimes it did. Often, the protocol merely moved the unit of account from one chain to another. Start with the ledger, not the event name A genuine protocol burn decreases the token contract’s totalSupply by destroying existing units. Ethereum’s EIP-1559 burn is a clear example: the base fee paid in ETH is destroyed, while validator rewards and priority fees are separate supply flows. ETH supply therefore depends on the balance between issuance and burned base fees. A transfer to an inaccessible “dead” address is different. It may remove tokens from practical circu...