Blockchain Fees
Know what to pay before you send. Get slow, standard and fast fee recommendations from the current mempool, EIP-1559 fees on EVM chains, and gas limit or compute unit estimates for transfers and contract calls.
Fee data for wallets and payout systems
Let users pick the speed
Show slow, standard and fast fees in your wallet, from the network's current mempool.
Size gas before signing
Estimate the gas limit of a native transfer, a token transfer or a contract call on EVM chains, and compute units on Solana.
Time your payouts
Check fees before a payout run, and send when the network is cheaper.
Make your first Blockchain Fees call
Real paths and example responses from the API reference. Add your API key and run it.
- Base URL
https://rest.cryptoapis.io - Auth: the X-API-Key header
- JSON responses, same shape on every chain
curl https://rest.cryptoapis.io/blockchain-fees/evm/ethereum/mainnet/mempool \ -H "X-API-Key: YOUR_API_KEY"
{
"slow": "0.000010",
"standard": "0.000015",
"fast": "0.000025",
"unit": "WEI"
}
curl https://rest.cryptoapis.io/blockchain-fees/utxo/bitcoin/mainnet/mempool \ -H "X-API-Key: YOUR_API_KEY"
{
"slow": "0.000010",
"standard": "0.000015",
"fast": "0.000025",
"unit": "BTC"
}
curl https://rest.cryptoapis.io/blockchain-fees/evm/ethereum/mainnet/eip-1559 \ -H "X-API-Key: YOUR_API_KEY"
{
"lastBlock": 19269503,
"baseFeePerGas": {
"unit": "WEI",
"value": "45265143502"
},
"maxFeePerGas": {
"fast": "75235090892",
"slow": "67416761254",
"standard": "69996407508",
"unit": "WEI"
},
"maxPriorityFeePerGas": {
"fast": "47085140300",
"slow": "37331114417",
"standard": "41987372497",
"unit": "WEI"
}
}
Every Blockchain Fees endpoint
Each operation links to its page in the API reference, with its parameters and responses. Paths take the blockchain and the network, so moving to another chain is a change of path.
/blockchain-fees/evm/{blockchain}/{network}/eip-1559/blockchain-fees/evm/{blockchain}/{network}/estimate-contract-interaction-gas-limit/blockchain-fees/evm/{blockchain}/{network}/estimate-native-coin-transfer-gas-limit/blockchain-fees/evm/{blockchain}/{network}/estimate-token-transfer-gas-limit/blockchain-fees/utxo/{blockchain}/{network}/mempool/blockchain-fees/utxo/{blockchain}/{network}/smart/blockchain-fees/solana/{network}/estimate-native-coin-transfer-compute-units/blockchain-fees/solana/{network}/estimate-program-invocation-compute-units/blockchain-fees/solana/{network}/estimate-token-transfer-compute-units/blockchain-fees/tezos/{network}/estimate-fa12-transferBlockchain Fees works on 19 blockchains
Mainnets, and test networks where the chain has one. Open a chain for its own endpoints and quick start.
Bitcoin
Ethereum
XRP Ledger
Ethereum Classic
Bitcoin Cash
Dash
Litecoin
Dogecoin
Zcash
BNB Smart Chain
Polygon
Tron
Solana
Tezos
Avalanche
Arbitrum
Optimism
Base
KaspaBlockchain Fees questions
Which blockchains does Blockchain Fees support?
Blockchain Fees works on 19 blockchains: Bitcoin, Ethereum, XRP Ledger, Ethereum Classic, Bitcoin Cash, Dash, Litecoin, Dogecoin, Zcash, BNB Smart Chain, Polygon, Tron, Solana, Tezos, Avalanche, Arbitrum, Optimism, Base, Kaspa. Each chain's page lists its networks and its own endpoints.
Can I try Blockchain Fees for free?
Yes, for 14 days. The Blockchain API free trial includes Blockchain Fees and every other feature, with no card. It ends after 14 days or when its credits run out; after that, calls need a subscription, listed on the pricing page.
Does the blockchain fees API support EIP-1559 gas fee recommendations for Ethereum?
Yes. For EVM chains such as Ethereum, Arbitrum, Base, and Optimism you can retrieve EIP-1559 style fee recommendations, including priority-based estimates. The API returns fee levels by priority (slow, standard, fast) so you can choose the tradeoff between cost and confirmation speed.
Can I estimate Bitcoin and other UTXO transaction fees with Crypto APIs?
Yes. The API provides fee recommendations for six UTXO chains: Bitcoin, Bitcoin Cash, Litecoin, Dogecoin, Dash, and Zcash. It returns recommended fee rates so you can build and broadcast a transaction with an appropriate fee for current network conditions.
Does the Crypto APIs fee API support Solana?
Yes. Fee recommendations are available for Solana, alongside EVM chains, UTXO chains, XRP, Tron, Tezos and Kaspa. The endpoint returns recommended fee levels so you can attach an appropriate fee before broadcasting.
Are testnets covered, or only mainnet fee data?
Both mainnet and testnet are supported for the covered chains. For example, Ethereum offers mainnet and Sepolia, Bitcoin offers mainnet and testnet, and XRP offers mainnet and testnet, so you can estimate fees in a test environment before going to production.
Start building with Blockchain Fees
14-day free trial, mainnet included. No card needed.