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Convert Fixed Width Text to CSV / Excel

Parse fixed-width / column-aligned text files into CSV or Excel by defining field widths. Runs entirely client-side.

100% Secure - your files are processed in your browser and never sent to a server.
Drop your file hereor click to browseSupports Text files (.txt) (Max 100MB)

How to use the Convert Fixed Width to CSV tool

  1. Load your data: Drag and drop your fixed-width text file, choose a file from your file explorer, or paste your data directly into the paste area.
  2. Configure column parsing: Enter comma-separated column widths (e.g. 10,20,15) or split positions (e.g. 10,30,45). Leave blank to auto-detect columns.
  3. Adjust output settings: Choose an output delimiter (comma, semicolon, tab, or pipe) and toggle whether the first row is a header.
  4. Convert to CSV: Click the "Convert Data" button to parse the fixed-width text into structured CSV.
  5. Export results: Copy the results to your clipboard, download as a local file, or export to Excel format.

Frequently asked questions

Is it safe to use Convert Fixed Width to CSV with sensitive or confidential data?
Yes, completely. All processing done by Convert Fixed Width to CSV runs 100% client-side inside your local web browser using a background Web Worker thread. Your data is never uploaded, transmitted, or stored on any server, not even temporarily.
What is the maximum file size Convert Fixed Width to CSV can handle?
Convert Fixed Width to CSV supports files up to 100 MB. Because all parsing happens inside your browser's memory rather than on a server, performance scales with your computer's available RAM. The Web Worker architecture keeps the UI fully responsive even during heavy processing.
How does Convert Fixed Width to CSV process my data without uploading it?
Convert Fixed Width to CSV uses modern browser File and Blob APIs alongside battle-tested open-source libraries (such as PapaParse and SheetJS) bundled directly into the page. When you load a file or paste data, the browser reads it into local memory and the conversion runs entirely inside a sandboxed Web Worker thread. No network call is ever made.
Do I need to install anything to use Convert Fixed Width to CSV?
No installation, browser extension, or plugin is required. Convert Fixed Width to CSV runs as a standard web page inside any modern browser. Simply open it, load your data, and download the output. Nothing to install and nothing to uninstall.
Does Convert Fixed Width to CSV work offline after the page has loaded?
Yes. Once Convert Fixed Width to CSV has finished loading in your browser, the conversion engine itself requires no active internet connection. You can disconnect from the network and continue converting files; all processing stays fully on-device.

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