A wrapped asset
Coinbase Wrapped BTC (cbBTC) is a wrapped ERC-20 token that tracks another asset on Base. Chainhook detects it as a token, separately from any native coin on the network.
Base cbBTC transfer notifications, delivered as webhooks
Get a signed webhook when a Base address sends or receives Coinbase Wrapped BTC (cbBTC). Chainhook waits 20 blocks, about 40 seconds, then posts the transfer to your endpoint.
cbBTC on Base at a glance
The contract Chainhook watches, how amounts are scaled, and how long cbBTC takes to reach your endpoint.
- Token
- Coinbase Wrapped BTC (cbBTC)
- Network
- Base
- Contract
0xcbb7c0000ab88b473b1f5afd9ef808440eed33bf- Decimals
- 8
- Confirmations
- 20
- Time to webhook
- About 40 seconds
How cbBTC ERC-20 webhooks work
Base blocks arrive every 2 seconds. A poller per address adds up quickly, and missed polls mean missed payments. Chainhook scans every block, waits 20 confirmations, and sends you one event per matching transfer.
Register the address
Create a webhook with
network: "base",type: "token"and the address you want to watch. The signing secret is returned once.Chainhook waits for confirmations
Every Base block is scanned. A matching cbBTC transfer is held until it is 20 blocks deep, about 40 seconds.
Your endpoint gets a signed POST
A
transfer.detectedevent arrives with anX-Webhook-Signatureheader. Failed attempts are retried automatically, up to 3 attempts in total, waiting 1 minute, then 5 minutes between attempts.
POST /v1/webhooks
{
"network": "base",
"type": "token",
"direction": "in",
"address": "0x5b8ddac816baad6111c7c7b39c88355c00ba7ea1",
"webhook_url": "https://api.example.com/webhooks/chainhook"
}Sample webhook payload
What your endpoint receives for an incoming cbBTC transfer on Base. amount is already scaled by decimals; amount_raw is the on-chain integer.
cbBTC on Base
POST /webhooks/chainhook HTTP/1.1 Host: api.example.com Content-Type: application/json User-Agent: chainhook/1.x X-Webhook-Id: 01a0fbfd-4fe4-7a3c-8f21-6b9d0e4c7a15 X-Webhook-Signature: 7a12d02673420517279805cf8188a1a62c6f69706161ba5cf0a8ec91ea66b8e3 { "id": "01a0fbfd-4fe4-7a3c-8f21-6b9d0e4c7a15", "event": "transfer.detected", "created_at": "2026-10-02T09:41:17Z", "webhook_id": "01a0fbf2-fadc-7c3e-9b1a-4d6f2e8a5c71", "data": { "network": "base", "direction": "in", "type": "token", "transaction_hash": "0xa83a048ea21fa019f5a9a0f35dfdf558a4edd9294ee0829e20302ebe6923c714", "transfer_index": 21, "block_number": 52887250, "block_hash": "0xbcbe46b5dc11274a52a9b7fbc0efbc0072cb7356bfe91f0cad9f618f3f24a9d8", "block_timestamp": "2026-10-02T09:41:05Z", "confirmations": 20, "from": "0x3c3facc56a38aab3314e6a46dc4f1c9f303b023e", "to": "0x5b8ddac816baad6111c7c7b39c88355c00ba7ea1", "currency": "cbBTC", "amount": "0.5", "amount_raw": "50000000", "decimals": 8, "contract_address": "0xcbb7c0000ab88b473b1f5afd9ef808440eed33bf" } }
Verify the signature
X-Webhook-Signature is a hex HMAC-SHA256 of the raw body, keyed with your webhook's secret. Reject any request where it doesn't match.
import crypto from 'node:crypto'; import express from 'express'; const app = express(); app.post( '/webhooks/chainhook', express.raw({ type: 'application/json' }), (req, res) => { const signature = req.get('X-Webhook-Signature') ?? ''; const expected = crypto .createHmac('sha256', process.env.CHAINHOOK_SIGNING_SECRET) .update(req.body) .digest('hex'); const valid = signature.length === expected.length && crypto.timingSafeEqual(Buffer.from(signature), Buffer.from(expected)); if (!valid) { return res.sendStatus(401); } const event = JSON.parse(req.body); // Skip event.id if you've already processed it. res.sendStatus(200); }, );
Crediting cbBTC deposits safely
Only this contract
Chainhook watches 0xcbb7c0000ab88b473b1f5afd9ef808440eed33bf. Versions of cbBTC bridged to Base through other routes are separate tokens and are not reported.
8 decimals
cbBTC on Base uses 8 decimals. Credit the amount string, or scale amount_raw by decimals; never parse amounts as floating-point numbers.
Credit once per transfer
Delivery is at least once. Store the event id, or transaction_hash with transfer_index, and skip events you have already processed.
Pay per detection
Start with 100 trial detections for 1 month and pay only for what you use. Paid plans add detections, webhooks, and per-detection overage.
Pay as you go
$0/month
Card required, no monthly fee
- 100 trial detections for 1 month
- 3 active webhooks
- $0.001 per detection after the trial
- Decoded transfers, delivered once confirmed
Starter
$9/month
or $90/year billed yearly
- 25,000 detections a month
- 25 active webhooks
- $0.0006 per extra detection
- Decoded transfers, delivered once confirmed
- Recommended
Growth
$29/month
or $290/year billed yearly
- 100,000 detections a month
- 100 active webhooks
- $0.0003 per extra detection
- Decoded transfers, delivered once confirmed
Scale
$99/month
or $990/year billed yearly
- 400,000 detections a month
- 200 active webhooks
- $0.0002 per extra detection
- Decoded transfers, delivered once confirmed
Enterprise
Custom limits for teams that need more than 400,000 detections a month or more than 200 active webhooks. Contact us and we'll set up a plan around your volume.
Prices in USD, plus applicable tax. Billed monthly or yearly, and paid allowances reset monthly. Cancel any time and keep your plan until the period ends.
cbBTC on Base questions
Can't find your answer? Contact support.
What is the cbBTC contract address on Base?
0xcbb7c0000ab88b473b1f5afd9ef808440eed33bf, with 8 decimals.
How do I detect an incoming cbBTC transfer on Base?
Create a webhook with network: "base", type: "token", direction: "in" and the receiving address. Each confirmed cbBTC transfer arrives as a transfer.detected event.
How long until a cbBTC transfer is reported?
About 40 seconds. Chainhook waits 20 blocks on Base before it sends the event.
Does Chainhook need my private key?
No. Chainhook only reads public blockchain data. You register a public address and receive events about it.
Watch your first wallet
Create an account and start with 100 trial detections for 1 month.