# Synapse API — Base Gas Estimation

> Synapse API — Base Gas Estimation is a paid API for AI agents from synapse-api-brown.vercel.app, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-24).

Estimates the gas cost for a transaction on the Base blockchain network given transaction parameters

## Facts

- Endpoint: POST https://synapse-api-brown.vercel.app/api/base/gas/estimate?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-24
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/synapse-api-base-gas-estimation-edf058b2
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ZQmTiEuy7U9wS7EhXx67X

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability synapse-api-base-gas-estimation-edf058b2 -d '<json body>'
```

Example prompt: Can you estimate how much gas it will cost to send 0.1 ETH on the Base network from 0xAbC123... to 0xDeF456... with no calldata?

## When to prefer this

Use this endpoint when you need a gas estimate specifically for the Base (Coinbase L2) network before submitting a transaction. Prefer this over generic gas estimators when working within the Base ecosystem, especially for smart contract interactions, token transfers, or NFT mints on Base. It is best used as a pre-submission check to avoid wasted fees or failed transactions.

## Known failure modes

- Invalid or malformed Ethereum address in 'to' or 'from' fields returns an error
- Malformed or non-hex 'data' field causes estimation failure
- Estimation may fail if the simulated transaction would revert on-chain
- Network unavailability or RPC errors from the Base node can return 5xx responses
- Missing required fields may return a 400 bad request

## How this service works

High-speed API suite for AI processing, web scraping, and smart data utilities across 57+ blockchain networks. Pay-per-call via x402.

## Output

Returns an estimated gas amount (in gas units) required to execute the described transaction on the Base network. This allows callers to budget for transaction fees before submission, check affordability, and avoid failed transactions due to insufficient gas.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "to": {
   "type": "string"
  },
  "data": {
   "type": "string"
  },
  "from": {
   "type": "string"
  },
  "value": {
   "type": "string"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/synapse-api-base-gas-estimation-edf058b2/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from synapse-api-brown.vercel.app](https://www.zero.xyz/host/synapse-api-brown.vercel.app/llms.txt)