Gas Estimator API
Multi-chain gas estimation — ETH, Base, Polygon, Arbitrum, BSC. x402 micropayment.
Open source Repository Open in the app JSON README (API)
About
Multi-chain gas estimation — ETH, Base, Polygon, Arbitrum, BSC. x402 micropayment.
Details
- Kind
- MCP servers
- Topic
- Finance & crypto
- Publisher
- br0ski777
- Origin
- official
- Category
- ferramentas
- Transport
- sse
- Version
- 1.1.0
- Last push
- 2026-09-02T19:56:03Z
- Repository state
- ativo
- Language
- TypeScript
- License
- MIT
- Added
- 2026-08-29 03:01:43
- Updated
- 2026-08-29 03:01:43
- Origin id
io.github.Br0ski777/gas-estimator
README
# Gas Estimator API
[](https://gas-estimator.api.klymax402.com/mcp)
[](https://x402.org)
[](LICENSE)
Multi-chain gas prices in one call -- ETH, Base, Polygon, Arbitrum, BSC. Compare chains to find cheapest. Pay-per-call via [x402](https://x402.org) (USDC on Base L2) -- no API key, no signup, no rate-limit wall.
Part of the [klymax402](https://klymax402.com) marketplace -- 100 x402 micropayment APIs for AI agents, one wallet, USDC on Base.
## Quickstart -- MCP
Add to your MCP client config (Claude Desktop, Cursor, ElizaOS, etc.):
```json
{
"mcpServers": {
"gas-estimator": {
"url": "https://gas-estimator.api.klymax402.com/mcp"
}
}
}
```
## Quickstart -- HTTP (x402)
```bash
curl -X POST "https://gas-estimator.api.klymax402.com/api/estimate" \
-H "Content-Type: application/json" \
-d '{}'
# -> 402 Payment Required, with an x402 payment challenge in the response body
```
Any x402-aware client ([`@x402/fetch`](https://www.npmjs.com/package/@x402/fetch), [`x402-agent-tools`](https://www.npmjs.com/package/x402-agent-tools), ATXP) handles the 402 -> sign -> retry cycle automatically.
## Tools
| Tool | Method | Path | Price | Description |
|---|---|---|---|---|
| `crypto_estimate_gas` | POST | `/api/estimate` | $0.005 | Get gas price estimates across multiple EVM chains with USD cost |
### `crypto_estimate_gas`
Use this when you need to compare gas prices across multiple EVM chains at once. Returns multi-chain gas estimates in JSON.
**Parameters**
| Name | Type | Required | Description |
|---|---|---|---|
| `chain` | string | no | Chain name: ethereum, base, polygon, arbitrum, bsc. Omit for all chains. |
**Returns**
- `chains` -- array of chain gas data with chain name
- `low` -- gas price in gwei for slow confirmation
- `medium` -- gas price in gwei for standard confirmation
- `high` -- gas price in gwei for fast confirmation
- `transferCostUsd` -- estimated USD cost for a simple transfer on each chain
- `cheapestChain` -- which chain currently has the lowest gas cost
Example response:
```json
{"chains":[{"chain":"base","low":0.005,"medium":0.008,"high":0.012,"transferCostUsd":0.01},{"chain":"ethereum","low":12.5,"medium":18.0,"high":25.0,"transferCostUsd":0.85}],"cheapestChain":"base"}
```
**When to use**: choosing the cheapest chain before a cross-chain transaction. Essential for multi-chain agents that need to optimize gas costs.
**Not for**: swap quotes (use `dex_get_swap_quote`), bridging (use `bridge_find_best_route`).
## Example agent prompts
- "Compare gas prices across multiple EVM chains at once"
## Payment
- Protocol: [x402](https://x402.org) -- HTTP-native pay-per-call, no signup, no API key
- Network: Base L2 (`eip155:8453`)
- Asset: USDC
- Facilitator: Coinbase CDP (primary), PayAI (fallback)
- Also reachable via [ATXP](https://atxp.ai) (OAuth-wrapped x402, RFC 9728 protected-resource metadata)
## Part of klymax402
100 x402 micropayment APIs for AI agents -- one wallet, USDC on Base, zero signup.
- Catalog: https://klymax402.com/llms.txt
- Full API reference: https://klymax402.com/llms-full.txt
- Live stats: https://klymax402.com/stats
## License
MIT