💬 Bitcoin Message Transaction Creator

Create Bitcoin transactions with embedded OP_RETURN messages. This tool allows you to permanently store text messages on the Bitcoin blockchain while sending BTC to any address.

🌟 Features

• ✅ OP_RETURN Message Embedding - Store up to 80 bytes of data on-chain
• ✅ Interactive UI - User-friendly interface in Google Colab
• ✅ CLI Version - Command-line interface for desktop use
• ✅ Automatic Change Calculation - Returns remaining funds to sender
• ✅ Testnet & Mainnet Support - Test safely before going live
• ✅ Transaction Export - Save RawTX to file for broadcasting
• ✅ Real-time Message Length Validation - Prevents errors before creation

📋 Table of Contents

• Installation- Usage - Google Colab Version - Python CLI Version- Broadcasting Transaction- Requirements- Examples- Security- Contributing- License---

🚀 Installation

Prerequisites

- Python 3.6 or higher
- Git

Clone Repository

git clone https://github.com/zoeir/Bitcoin-Message-Transaction.git
cd Bitcoin-Message-Transaction

Install Dependencies

pip install ipywidgets zmq urllib3 requests pycryptodome

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📖 Usage

🌐 Google Colab Version

https://colab.research.google.com/drive/1tw9y8FXSwaEYYfNnC7jwiqTdVatUiqIV

Perfect for users who want a graphical interface without installing anything locally.

Step 1: Open Google Colab

Navigate to Google Colab

Step 2: Create New Notebook

Click File → New Notebook

Step 3: Install Dependencies

Copy and paste this code into the first cell:

!pip install ipywidgets zmq urllib3 requests pycryptodome
!git clone https://github.com/zoeir/Bitcoin-Message-Transaction.git > /dev/null 2>&1
%cd Bitcoin-Message-Transaction

Run the cell (press Shift + Enter)

Step 4: Load the Script

In a new cell, copy the entire content of colab.py and run it.

Step 5: Fill the Form

An interactive form will appear with the following fields:

| Field | Description | Example |
|-------|-------------|---------|
| 🔑 **Private Key (WIF)** | Your Bitcoin private key in WIF format | `5J64pq77XjeacCezwmAr2V1s7snvvJkuAz8sENxw7xCkikceV6e` |
| 🆔 **UTXO TXID** | Transaction ID containing your funds | `2a29fdb4e188f827da3c3175856b3ed95819b323bb303a46b8036534e78c76db` |
| 🔢 **UTXO Index** | Output index (usually 0) | `0` |
| 💰 **UTXO Value** | Amount in satoshi | `30352330` |
| 💸 **Transaction Fee** | Network fee (500-10000 sat) | `1000` |
| 📤 **Send Amount** | Amount to send in satoshi | `600` |
| 📍 **Recipient Address** | Destination Bitcoin address | `1LdRcdxfbSnmCYYNdeYpUnztiYzVfBEQeC` |
| 💬 **Message** | Your text message (max 80 bytes) | `Hello Bitcoin!` |
| 🧪 **Use Testnet** | Enable for testing | ☑️ Checked |

Step 6: Create Transaction

Click "Create Bitcoin Transaction" button

Step 7: Copy RawTX

The output will display:

• ✅ Your BTC Address- ✅ Recipient Address - ✅ Send Amount- ✅ Transaction Fee- ✅ Change Returned- ✅ OP_RETURN Message- ✅ RawTX (Hex) ← Copy this for broadcasting---

🖥️ Python CLI Version

For users who prefer command-line interface on their desktop/laptop.

Step 1: Navigate to Repository

cd Bitcoin-Message-Transaction

Step 2: Run the Script

python3 main.py

Step 3: Follow Interactive Prompts

The script will ask for:

=================================
BITCOIN MESSAGE TRANSACTION CREATOR
Enter your Private Key (WIF): 5J64pq77Xjeac...

--- UTXO Information ---
Enter UTXO TXID: 2a29fdb4e188f827...
Enter UTXO Index (default 0): 0
Enter UTXO Value (satoshi): 30352330

--- Transaction Details ---
Enter Recipient Address: 1LdRcdxfbSnmCYYNdeYpUnztiYzVfBEQeC
Enter Send Amount (satoshi): 600
Enter Transaction Fee (satoshi, default 1000): 1000

--- OP_RETURN Message ---
Enter your message (up to 80 bytes): Hello Bitcoin!

--- Network Selection ---
Use Testnet? (y/n, default y): y

Step 4: Review Output

============================================================
BITCOIN TRANSACTION (OP_RETURN)
Your BTC Address: 14NWDXkQwcGN1Pd9fboL8npVynD5SfyJAE
Recipient Address: 1LdRcdxfbSnmCYYNdeYpUnztiYzVfBEQeC
Send Amount: 600 satoshi
Transaction Fee: 1000 satoshi
Change Returned: 30350730 satoshi

OP_RETURN Message: Hello Bitcoin!

RawTX (Hex):
0100000001db768ce7346503b8463a30bb23b31958d93e6b8575313cda..
============================================================

✓ Transaction saved to file: RawTX_OP_RETURN.txt

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📡 Broadcasting Transaction

After creating your transaction, broadcast it using any of these services:

Mainnet Services

Service	URL
🌐 Bitcoin Message	bitcoinmessage.ru

Steps:

1. Copy your RawTX (Hex) from the output
2. Visit any broadcast service above
3. Paste the RawTX into the form
4. Click "Broadcast" or "Push"
5. Wait for confirmation

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📦 Requirements

Python Packages

• pycryptodome - Cryptographic library
• ipywidgets (Colab only) - Interactive widgets
• IPython (Colab only) - Display utilities

Repository Dependencies

This tool requires modules from Bitcoin-Message-Transaction:

• secp256k1.py - Elliptic curve operations
• sighash.py - Transaction signing

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💡 Examples

Example 1: Simple Message

Message: "Hello from the blockchain!" Send Amount: 1000 satoshi Fee: 1000 satoshi

Example 2: Timestamp Proof

Message: "Document hash: 5d41402abc4b2a76b9719d911017c592" Send Amount: 546 satoshi (dust limit) Fee: 2000 satoshi

Example 3: Identity Proof

Message: "github.com/zoeir/Bitcoin-Message-Transaction/ - Verified 2025" Send Amount: 600 satoshi Fee: 1500 satoshi

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🔒 Security

⚠️ Important Security Notes

• Never share your private key with anyone
• Test on Testnet first before using real BTC
• Double-check addresses before broadcasting
• Backup your private keys securely offline
• Use secure connections when broadcasting transactions
• OP_RETURN data is permanent and cannot be deleted

Best Practices

1. ✅ Use testnet for testing
2. ✅ Verify recipient address multiple times
3. ✅ Start with small amounts
4. ✅ Keep private keys in encrypted storage
5. ✅ Never commit private keys to Git

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Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

Development Setup

git clone https://github.com/zoeir/Bitcoin-Message-Transaction.git
cd Bitcoin-Message-Transaction
pip install -r requirements.txt

Reporting Issues

Please use the GitHub Issues page to report bugs or request features.

---## 📄 LicenseThis project is licensed under the MIT License - see the LICENSE file for details. ---## 🙏 Acknowledgments- Bitcoin Core developers

• Bitcoin-Message-Transaction repository
• Python cryptography community---## 📞 Support- 🌐 Website: bitcoinmessage.ru
• 📧 Issues: GitHub Issues
• 💬 Discussions: GitHub Discussions---## ⭐ Star HistoryIf you find this project useful, please consider giving it a star! ⭐---Made with ❤️ for the Bitcoin community---## 📸 Screenshots

Google Colab Interface

CLI Version Output

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📊 Statistics

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