# Synapse API — opBNB Gas Estimator

> Synapse API — opBNB Gas Estimator 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 2026-09-13).

Estimates gas cost for a transaction on the opBNB blockchain network given sender, recipient, data, and value

## Facts

- Endpoint: POST https://synapse-api-brown.vercel.app/api/opbnb/gas/estimate
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/synapse-api-opbnb-gas-estimator-f5b34c94
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_DXyX8SmoLwPIl1uJymVsZ

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-opbnb-gas-estimator-f5b34c94 -d '<json body>'
```

Example prompt: Estimate the gas needed for a transaction on opBNB from 0xAbC123... to 0xDeF456... with no calldata and a value of 0.01 BNB.

## When to prefer this

Use this endpoint when you specifically need gas estimates for the opBNB (BNB Chain Layer 2) network. It is purpose-built for opBNB and will not apply to Ethereum mainnet, BSC, or other chains. Prefer this over generic blockchain tools when you want a pay-per-call, infrastructure-free gas estimation without running your own node.

## Known failure modes

- Invalid or malformed 'to' or 'from' address returns an error response
- Malformed calldata in 'data' field may cause estimation failure or revert simulation
- Network unavailability or opBNB RPC issues may result in timeout or 503 error
- Missing required fields may return a 400 Bad Request
- Transaction that would revert on-chain may return an error or inflated estimate

## 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 specified transaction on the opBNB network, enabling callers to calculate expected transaction fees before submission.

## 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-opbnb-gas-estimator-f5b34c94/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)