Multi-chain EVM gas price oracle for AI agents — 17 chains (Ethereum, Base, Arbi
Multi-chain EVM gas price oracle for AI agents — 17 chains (Ethereum, Base, Arbitrum, Optimism, Polygon, BNB, Avalanche…). One x402 call returns slow/standard/fast EIP-1559 tiers as DROP-IN maxFeePerGas + maxPriorityFeePerGas in wei (plug straight into a viem/ethers tx, no conversion, exact even on sub-gwei L2s), plus base fee, head block, and fullness, from a live eth_feeHistory call. Pass ?chain= to switch chains.
Answeringour last check, 2026-09-24
1 of 1checks answered this week
928 msmedian answer time
$0.001listed price per call
$0.001price it asked us
Paid test badge: not yet. The checks above are free: we call the tool without paying and read the payment request it sends back. The Verified badge needs paid calls whose answers match the promised output, and nobody can buy a badge.
Endpoint
GET https://evm-gas.apitoll.cloud/v1/evm/gas
| Category | Market data |
|---|---|
| Provider host | evm-gas.apitoll.cloud |
| Networks | eip155:8453 |
| Payment schemes | exact |
| Self-reported calls, 30 days | 13 from 10 payers (the provider's figure, not ours) |
Our checks, last 30 days
| Day | Result | HTTP | Asked | Time |
|---|---|---|---|---|
| 2026-09-24 | valid payment request | 402 | $0.001 | 928 ms |
Example input (from the provider)
{
"method": "GET",
"queryParams": {
"blocks": 20,
"chain": "ethereum"
},
"type": "http"
}
Promised output schema (from the provider)
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"input": {
"additionalProperties": false,
"properties": {
"method": {
"enum": [
"GET"
],
"type": "string"
},
"queryParams": {
"properties": {
"blocks": {
"description": "Recent blocks to sample for percentile reward (1..50, clamped).",
"maximum": 50,
"minimum": 1,
"type": "integer"
},
"chain": {
"description": "Target EVM chain id. One of: ethereum, base, optimism, arbitrum, polygon, avalanche, gnosis, linea, scroll, blast, mode, opbnb, celo, bsc, fantom, zksync, mantle. Also accepts common aliases (eth, arb, op, matic, avax, bnb). Default: ethereum.",
"enum": [
"ethereum",
"base",
"optimism",
"arbitrum",
"polygon",
"avalanche",
"gnosis",
"linea",
"scroll",
"blast",
"mode",
"opbnb",
"celo",
"bsc",
"fantom",
"zksync",
"mantle"
],
"type": "string"
}
},
"required": [
"chain"
],
"type": "object"
},
"type": {
"const": "http",
"type": "string"
}
},
"required": [
"type",
"method"
],
"type": "object"
},
"output": {
"properties": {
"example": {
"properties": {
"base_fee_gwei": {
"description": "Base fee for the next block (gwei, human-readable).",
"type": "number"
},
"base_fee_wei": {
"description": "Base fee in wei (exact, BigInt-ready decimal string).",
"type": "string"
},
"block_number": {
"type": "integer"
},
"caip2": {
"type": "string"
},
"chain": {
"enum": [
"ethereum",
"base",
"optimism",
"arbitrum",
"polygon",
"avalanche",
"gnosis",
"linea",
"scroll",
"blast",
"mode",
"opbnb",
"celo",
"bsc",
"fantom",
"zksync",
"mantle"
],
"type": "string"
},
"chain_name": {
"type": "string"
},
"gas_model": {
"enum": [
"eip1559",
"mostly-legacy",
"non-standard"
],
"type": "string"
},
"gas_note": {
"type": "string"
},
"stats": {
"properties": {
"blocks_sampled": {
"type": "integer"
},
"median_fullness_pct": {
"type": "number"
},
"ts": {
"format": "date-time",
"type": "string"
}
},
"type": "object"
},
"tiers": {
"description": "Slow (p10) / standard (p50) / fast (p90) EIP-1559 fee tiers. Each carries human gwei (max_fee_gwei/max_priority_gwei) AND DROP-IN wei (maxFeePerGas/maxPriorityFeePerGas, BigInt-ready) to plug straight into a viem/ethers tx.",
"properties": {
"fast": {
"properties": {
"maxFeePerGas": {
"type": "string"
},
"maxPriorityFeePerGas": {
"type": "string"
},
"max_fee_gwei": {
"type": "number"
},
"max_priority_gwei": {
"type": "number"
}
},
"type": "object"
},
"slow": {
"properties": {
"maxFeePerGas": {
"type": "string"
},
"maxPriorityFeePerGas": {
"type": "string"
},
"max_fee_gwei": {
"type": "number"
},
"max_priority_gwei": {
"type": "number"
}
},
"type": "object"
},
"standard": {
"properties": {
"maxFeePerGas": {
"type": "string"
},
"maxPriorityFeePerGas": {
"type": "string"
},
"max_fee_gwei": {
"type": "number"
},
"max_priority_gwei": {
"type": "number"
}
},
"type": "object"
}
},
"type": "object"
}
},
"type": "object"
},
"type": {
"type": "string"
}
},
"required": [
"type"
],
"type": "object"
}
},
"required": [
"input"
],
"type": "object"
}