free · in-browser · no upload

DAT to CSV
Converter

Drop your DAT file. We'll convert it to CSV right here in your browser, your file never leaves your device.

or drop your file

Select your file here to get started

or drop your file here.

Accepts .dat

nothing uploaded no file size cap no signup

How it works

Three steps. No upload, no signup.

1
Drop your file
Click the dropzone above or drag a DAT from your desktop. Files of any size, there's no upload, so there's no upload limit.
2
Convert in your browser
The conversion runs entirely in this tab using JavaScript and WebAssembly. Your file never touches our servers, we don't have any.
3
Download
Get your CSV the moment the conversion finishes. Convert another, or close the tab.

Files stay on your device

Your file is never uploaded. The entire conversion runs in your browser using WebAssembly. We can't see what you convert because we have no server to see it.

No file size limit

Server converters cap free users at 1-2 GB and gate larger files behind a paid plan. Since nothing uploads, our limit is whatever your browser can handle.

Free, no signup, no ads on conversions

No account required. No watermark on the output. No queue. Drop a file, get a converted file.

Why convert DAT → CSV

What this conversion is actually for

Receiving a production from opposing counsel means a folder of DAT load files that Excel renders as garbage (those mysterious þ characters are U+00FE text qualifiers, paired with U+0014 field delimiters). Converting to CSV is the first step every paralegal does to triage what's been produced — count documents, sort by date, search for hot terms in extracted text — before the formal review platform load.

A real example

You receive a 50,000-document production from opposing counsel as a DAT + OPT pair. Before loading into Relativity (which costs your client per GB hosted), you want to spot-check what's there. Convert the DAT to CSV, sort by `EmailFrom`, and pull out the 200 communications between two specific custodians for an early-case strategy review.

Troubleshooting

Extracted text fields contain literal newlines that break my CSV import.

DAT extracted-text fields routinely contain embedded newlines (paragraph breaks in emails, attachments). We preserve them inside CSV cells, properly quoted per RFC 4180. If your downstream tool can't handle multi-line cells, replace `\n` with ` ` in the extracted-text column post-conversion.

My DAT uses `|` delimiters instead of the Unicode characters.

Older Concordance exports (pre-2010) sometimes use pipe-and-comma fallbacks. We auto-detect: if no U+0014 characters appear in the input, we fall back to `|` as field delimiter. If your file uses something else entirely (rare), pre-process with sed or open in a hex editor to confirm the delimiter byte.

Bates numbers got reformatted (leading zeros dropped).

Excel auto-detects Bates numbers like `ABC0000123` as text correctly, but plain CSV import sometimes treats numeric-looking values as numbers and strips leading zeros. We preserve them as text in the CSV output. If your spreadsheet still strips them, use Excel's Import Wizard and explicitly set the Bates column to Text type.

Formats involved

About DAT and CSV

DAT, Concordance/Relativity load file

DAT is the metadata + extracted-text load file format every U.S. eDiscovery production uses. Produced by Concordance, Relativity, Reveal, Logikcull, Everlaw, and every law firm review platform. Uses non-printable Unicode characters (U+0014 field delimiter, U+00FE text qualifier) instead of CSV's commas + quotes — the unusual delimiters avoid collisions with quoted text inside fields like email body content. CRLF line terminators (Concordance is Windows-native).

How to open

Concordance, Relativity, Reveal, Everlaw, Logikcull, and every other eDiscovery review platform load DAT files natively. Excel opens them but shows garbled þ characters. Convert to CSV for spreadsheet workflows; the original DAT remains the production-of-record format.

Full DAT format guide →

CSV, Comma-Separated Values

CSV is plain text, one row per line, fields separated by commas. The simplest possible tabular data format, which is exactly why it remains the most portable: every spreadsheet, database, programming language, and analytics tool reads CSV. Tradeoffs: no formulas, no formatting, no multiple sheets, and various edge cases around quoting fields that contain commas or newlines.

How to open

Excel, Google Sheets, Apple Numbers, LibreOffice Calc, any text editor, every database import wizard, every programming language with one line of code.

Full CSV format guide →

Related tools

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FAQ

Common questions

Is this DAT → CSV converter really free?

Yes. No signup, no watermark, no daily file count limit. Every conversion runs in your browser, your file never touches our servers because there are no servers.

Where does my file go when I convert it?

Nowhere. The conversion runs entirely in your browser using JavaScript and WebAssembly. Your file is never uploaded to our servers. We don't have any servers handling files, there's nothing for us to log, store, or accidentally leak.

What's the maximum file size?

Whatever your browser can hold in memory. Practically, this means a few hundred MB on most computers, significantly larger than the 1-2 GB caps that server-upload converters charge for. Very large files (multi-GB) may require closing other browser tabs first.

Why convert DAT to CSV?

eDiscovery document production metadata exchange between law firms. Universal tabular data interchange. The most common reason to convert is compatibility, CSV works in places where DAT doesn't, or vice versa.

How do I open a DAT file in the first place?

Does this work offline?

Once the page is loaded, the conversion itself runs entirely offline. The first time you use a tool, your browser downloads the conversion library (a one-time cache). If you reload while offline, the page won't load, but you can install the site as a Progressive Web App for full offline use.

Can I convert multiple files at once?

Single file at a time for now. Batch conversion is on the roadmap, for now, drop one file, download the result, then convert the next.

DAT to CSVConverter