Split CSV by MB

A specific megabyte target, 50 MB, 100 MB, whatever number matters for your situation, is sometimes the exact constraint you need to design around, and a splitter that lets you enter that number directly removes any guesswork about how many rows would translate to roughly that size.

Turbo CSV Splitter's File Size method lets you set exactly the target size in MB your situation calls for. The tool rolls over to a new output part as soon as the current one reaches your specified size, so you don't need to estimate row counts to hit a byte-based target.

Because rows vary in width, especially in CSV files with mixed-length text fields, a size-based split produces files that stay close to your target MB even when a row-count-based approach would have produced wildly different actual file sizes across parts.

This is particularly useful for matching output directly to a known constraint, an upload portal's stated MB limit, an email provider's attachment cap, or a a specific size a downstream system expects, without any trial-and-error row-count guessing.

The header is repeated at the top of every size-based part, so each output file remains independently valid no matter how many rows happened to fit before your specified size was reached.

Everything runs offline, on your own Windows PC, so splitting a file to a custom MB size never requires uploading the file anywhere to test whether the resulting parts actually fit your target. Delimiter and encoding both default to Auto and are detected directly from the file itself, so you only need to touch them in the rare case detection gets something wrong, an unusual delimiter or a legacy encoding, for example. This makes the tool equally useful for data analysts working with irregular exports, developers automating a recurring pipeline step, e-commerce teams distributing catalog data by category, and anyone else who regularly runs into the practical limits of opening a large CSV file directly in a spreadsheet program.

1. Install Turbo CSV Splitter on your Windows PC.
2. Browse to or drag and drop your CSV file.
3. Choose your output folder.
4. Select the File Size split method.
5. Enter your custom target size in MB.
6. Run Preview to confirm the setup.
7. Click Start Split and monitor progress.
8. Open the output folder to find your custom-sized files.
9. Adjust the parallel worker slider (1-128) if compressing many output parts.
10. Check the status bar for the final row count and file count summary.

• Set any custom target size in MB for output files
• No need to estimate row counts to hit a byte-based target
• Files roll over automatically once the target size is reached
• Header repeated on every custom-sized part
• Matches output directly to known upload or attachment limits
• Works regardless of row width variation in the source file
• Runs fully offline with no uploads required
• One-time purchase for Windows, with Gumroad license activation
• Compression options: uncompressed, per-part ZIP/gzip, or a single bundled archive
• Works with files on local drives, external drives, and network shares