# BaseBuilder Crypto Gas Estimate

> BaseBuilder Crypto Gas Estimate is a paid API for AI agents from bb-crypto.vercel.app, paid per call via x402, $0.074561/call, status unknown (last checked 2026-09-16).

Estimates gas fees for a crypto transaction on the Base blockchain

## Facts

- Endpoint: POST https://bb-crypto.vercel.app/api/gas-estimate
- Price: $0.074561/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-16
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/basebuilder-crypto-gas-estimate-d8fe529b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_1OhEQHCFzAtuSEy-GUSaG

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 basebuilder-crypto-gas-estimate-d8fe529b -d '<json body>'
```

Example prompt: Can you estimate how much gas it will cost to call this smart contract function on the Base network — the contract is at 0xAbC123... and I want to call the transfer function with 100 USDC?

## When to prefer this

Use this endpoint when you need to estimate gas costs for transactions specifically on the Base L2 network before submitting them, especially for smart contract interactions. Prefer this over generic gas trackers when you need a computation-specific estimate rather than a network-wide average.

## Known failure modes

- Invalid contract address returns 400 error
- Malformed transaction data causes estimation failure
- Network congestion may cause stale gas price estimates
- Contract not deployed on Base returns not-found error
- Missing required transaction fields returns validation error

## How this service works

BaseBuilder Crypto API hub - 26 paid endpoints

## Output

Returns an estimated gas limit and gas price for the specified transaction on the Base network, typically including the estimated total fee in both ETH and USD equivalent, allowing the user to understand the cost before submitting the transaction on-chain.

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/basebuilder-crypto-gas-estimate-d8fe529b/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from bb-crypto.vercel.app](https://www.zero.xyz/host/bb-crypto.vercel.app/llms.txt)