# Broadcast a signed transaction

Paste a signed raw transaction and send it to the network, without running a node. The broadcast tool is coming soon, free and with no signup. You sign the transaction yourself, so we never see your keys.

- Free
- No signup
- We never ask for a private key
- **Transaction ID** Returned when the network accepts the transaction.
- **Network** The one you picked, checked against the transaction.
- **Next step** Follow the confirmation on an explorer, or with a webhook.

### Broadcast from your code

The broadcast API sends signed transactions on the chains in its documentation. It is live today, with the same API key as the rest of the Blockchain API.

```
curl -X POST https://rest.cryptoapis.io/
  broadcast-transactions/tron/mainnet \
  -H "X-API-Key: YOUR_API_KEY" \
  -d '{"data":{"item":{"signedTransactionHex":"0a02…f29b01"}}}'
```

```
{
  "transactionId": "347d9685…e0a2"
}
```

- **You sign, we send.** The tool takes a transaction you already signed. It never asks for a private key or a seed phrase.
- **Read-only check.** We look up public blockchain data. Nothing is sent or stored on-chain.
- **Crypto APIs, Inc.** Delaware, USA. Building blockchain APIs since 2018.
- **ISO 27001 certified.** Independently audited information security.

## What does broadcasting a transaction mean?

Broadcasting sends a signed transaction to the network's nodes, so a miner or validator can include it in a block. A wallet usually does this for you. A broadcast tool sends a transaction you signed somewhere else, for example on an offline machine.

- Send a transaction signed on an offline or air-gapped machine
- Send without running or syncing a node
- A signed transaction holds no private key, so it is safe to share

### From unsigned to confirmed

| Step | What it means | Who does it |
| --- | --- | --- |
| Prepare | Build the unsigned transaction: sender, recipient, amount and fee. | You, or the prepare API |
| Sign | Add the signature with the private key. | You, on your own machine |
| Broadcast | Send the signed transaction to the network. | This tool, or the broadcast API |
| Confirm | A block includes the transaction. | The network |

## How will the broadcast tool work?

### Sign the transaction

With your wallet, your own code or the offline signer.

### Paste the hex

Copy the signed raw transaction into the field.

### Pick the network

Choose the chain and network the transaction is for.

### Send it

Get the transaction ID and follow the confirmation.

## Build the whole flow, without custody

### Broadcast transactions

Send signed transactions from your code. Live today.

### Offline signer

Sign transactions on your own server with an open-source library. No API key, no network call.

### Prepare transactions

Get an unsigned transaction with the fee and nonce worked out, ready to sign.

## Broadcast questions

### What is a signed raw transaction?

It is a transaction that is already signed with the sender's private key, written as hex. It holds the recipient, the amount, the fee and the signature, but not the private key itself.

### Is it safe to paste a signed transaction?

Yes. A signed transaction cannot be changed without breaking its signature, and it holds no private key. Anyone who has it can only send it exactly as it is.

### Which networks will the tool support?

Bitcoin, Ethereum, Tron, BNB Smart Chain and Polygon are planned, and the final list is confirmed at launch. The broadcast API is live today; its chains are listed in its documentation.

### Is the broadcast tool free?

Yes. It will be free, with no signup. It is coming soon; request access and we will tell you when it is live.

### Why would a broadcast fail?

The most common reasons are a fee that is too low, a nonce or input that was already used, or a transaction signed for a different network. The network's error message tells you which.

### Can I broadcast from my code today?

Yes. Send the signed hex to the broadcast API with your API key. Prepare the transaction with the API, sign it on your own server, then broadcast it: we never hold your keys.

## The broadcast tool is coming soon

Free, with no signup. Request access and we will tell you when it is live, or broadcast from your code today.