📬 MBOX Splitter

A fast and efficient Python tool for splitting large .mbox email archive files into smaller chunks. Designed to prevent issues with oversized mailbox files and improve email management.

🚀 Features

✅ Splits large .mbox files into smaller parts based on size (MB)
✅ Preserves email integrity and format
✅ Real-time progress tracking with a dynamic progress bar
✅ Automatically names output files sequentially (file_1.mbox, file_2.mbox, etc.)
✅ Works efficiently with large .mbox files

📌 Requirements

Make sure you have Python 3.x installed. Additionally, install the required dependencies:

pip install tqdm

📥 Installation

Clone the repository and navigate to the project folder:

git clone https://github.com/gray-area/mbox-splitter.git cd mbox-splitter

🔧 Usage

Move .mbox file into MBOX Splitter folder

Run the script with the following command:

python splitter.py <filename.mbox> <size_in_MB>

📌 Example

Splitting a backup.mbox file into 50MB chunks:

python splitter.py backup.mbox 50

📤 Output

The tool will generate new .mbox files in the same directory:

backup_1.mbox (≈ 50MB) backup_2.mbox (≈ 50MB) backup_3.mbox (remaining size)

⏳ Progress bar

For example if the input mbox file is 11GB and the output chucks are of 1024 MB = 1GB.

Splitting `backup.mbox` into chunks of 1024 MB...

Processing Data:   9%|█▊                  | 1.07G/11.7G [00:53<08:09, 21.7MB/s]Created file `backup_1.mbox`, size=1025MB, approx messages=1749.
Processing Data:  18%|███▋                | 2.15G/11.7G [01:54<06:22, 24.9MB/s]Created file `backup_2.mbox`, size=1026MB, approx messages=1746.
Processing Data:  28%|█████▌              | 3.23G/11.7G [02:43<05:53, 23.9MB/s]Created file `backup_3.mbox`, size=1025MB, approx messages=2070.
Processing Data:  37%|███████▎            | 4.30G/11.7G [03:40<04:05, 30.1MB/s]Created file `backup_4.mbox`, size=1025MB, approx messages=1686.
...
Created file `backup_11.mbox`, size=868MB, approx messages=3083.

Done.

🛠️ How It Works

1. Reads the .mbox file message by message.

2. Calculates each email’s size in bytes.

3. Writes messages into a new .mbox file until it reaches the specified size.

4. Creates a new .mbox file and continues processing.

🐍 Compatibility

✅ Python 3.x
✅ Works on Windows, macOS, and Linux

🏆 Contributing

Feel free to fork this repo and submit a pull request! Any contributions, suggestions, or improvements are welcome.

📜 License

MIT License. See LICENSE for details.

📧 Contact

For questions or support, open an issue on GitHub.

🚀 Enjoy hassle-free .mbox splitting! 🎯