Fixed-width output

CSV to Fixed Width Text Converter

Convert CSV to fixed-width text, padding every column to a set width so the data lines up perfectly in a monospaced view. Ideal for mainframe feeds, reports and legacy fixed-length formats.

FreeNo sign-upRuns in your browserExcel-friendly
CSV to Fixed Width Text Converter
Paste or upload text to convert.
Input — paste or upload
Drag a file here, or browse (.txt, .csv, .tsv, .json)
Output
Input is
Input delimiter
Column widths
Output as
Custom delimiter
Plain text style
Quoting
Line ending

A live table preview of your data appears here.

Output is fixed-width — each column is padded to its widest value automatically.

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What it does

Convert CSV into fixed-width text

Fixed-width (fixed-length) text aligns every column by character position instead of using a separator — still required by many mainframe, banking and reporting systems. To convert CSV to fixed width text file, this tool measures each column and pads the values so they line up.

Paste or upload your CSV and the converter computes each column’s width from its longest value, then writes aligned rows. The result looks like a clean table in any monospaced editor and is ready for systems that parse by position.

Going the other way — reading fixed-width text into CSV — is handled by fixed width to CSV. For other separators, see CSV to delimited text.

Step by step

How to use it

Paste or upload

Add your text or drop a file — it is read locally in your browser, never uploaded.

Preview & adjust

Check the live table and the row / column counts, then tweak the delimiter or options if a column looks off.

Copy or download

Grab the result with Copy or Download. You can reopen recent conversions from this device too.

Example

Input and output example

CSV padded into fixed-width columns that line up in a monospaced view.

Input
id,name,city
1,Ada,NY
20,Lin,LA
Output
id  name  city
1   Ada   NY
20  Lin   LA
Details

How columns are aligned

Consistent widths make the file readable and machine-parseable.

Automatic column widths

The converter scans every row to find the longest value in each column, then pads all values in that column to match, adding a space of separation. The output aligns cleanly without you measuring anything.

Reading it back

Because the widths are consistent, systems that parse by position can read the file reliably. If you later need it as CSV again, the fixed width to CSV tool can auto-detect the same boundaries.

Monospaced viewing

View the result in a monospaced font (most code editors) to see the columns line up. Proportional fonts will not show the alignment correctly even though the file is valid.

Encoding

Output is UTF-8. Note that multi-byte characters occupy one character position here, which is the usual convention for text alignment.

Good to know

Fixed-width text, then and now

Fixed-width formats predate delimited files and still anchor a surprising amount of infrastructure in banking, government and insurance. Their appeal is determinism: because every field occupies a known range of character positions, a reader never has to guess where one column ends and the next begins, and there is no delimiter to collide with the data. Converting a CSV to fixed-width text lets modern, comma-based data flow into those systems unchanged. The key is consistency, which this tool guarantees by padding each column to the width of its longest value. When a downstream specification dictates exact widths, keep that in mind — you may need to pad the source so columns match the required layout. View the output in a monospaced font to confirm the alignment, and remember the fixed-width-to-CSV tool reverses the process whenever you need the data back as CSV.

FAQ

CSV to Fixed Width Text Converter — FAQ

How are column widths chosen?

Each column is padded to the width of its longest value, with a space of separation.

What is fixed-width text used for?

Mainframe feeds, banking files and legacy reports that parse data by character position.

Why doesn’t it line up in my viewer?

Use a monospaced font; proportional fonts will not show the alignment.

Can I convert it back to CSV?

Yes, use the fixed width to CSV tool.