Sometimes you need to import Fixed-Width Text to MongoDB, you can use Withdata FileToMongo as fixedwidth to MongoDB Converter (Importer / Loader).
Works GREAT on Windows, Mac and Linux.
Support Windows, Linux, and macOS.
Support all MongoDB deployment types: standalone, replica set, sharded cluster, and MongoDB Atlas.
Can run in GUI mode, Step by Step, just a few mouse clicks.
Can run in CLI (Command Line Interface), for Scheduled Tasks and Streams, for Automation.
Start Withdata FileToMongo, connect to MongoDB.

Click "1 File To 1 Collection" at task dialog.

Select the "Fixed-Width Text" file type.

1. Open a Fixed-Width Text file.

The source Fixed-Width Text file like this:

2. Choose collection and map columns.

3. Preview and set rows options.

4. Import Fixed-Width Text to MongoDB collection.

After importing, you can view imported data in MongoDB collection.

Click "N File To 1 Collection" at task dialog.

Select the "Fixed-Width Text" file type.

1. Open Fixed-Width Text folder.

2. Set Fixed-Width Text options.

3. Choose collection and map columns.

4. Preview and set rows options.

5. Import Fixed-Width Text to MongoDB collection.

After importing, you can view imported data in MongoDB.

Click "N File To N Collection" at task dialog.

then show the wizard.
Select the "Fixed-Width Text" file type.

1. Open Fixed-Width Text folder.

2. Set Fixed-Width Text options.

3. List collesions, set "Import Type".

4. Map files to collections.

5. Summary.

6. Import Fixed-Width Text data to MongoDB collections.

After importing, you can view imported data.

After importing Fixed-Width Text to MongoDB in GUI, and Saving "Fixed-Width Text to MongoDB" session, then you can:
After importing Fixed-Width Text to MongoDB in Command Line, then you can schedule and automate "Fixed-Width Text to MongoDB" conversion task by:
How long does it take to import Fixed-Width Text to MongoDB?
Is it safe to import Fixed-Width Text to MongoDB using FileToMongo?
Can I import Fixed-Width Text to MongoDB on Linux, Mac OS?
Can I import Fixed-Width Text to MongoDB in command line?
Can I batch import Fixed-Width Text files to MongoDB collections?