Open files in VS Code and Cursor / Developer files

Read an X12 or EDIFACT file in VS Code

EDI Viewer shows an X12 or EDIFACT file in VS Code as a tree of interchanges, groups, transaction sets, loops and segments. Click a segment to see each element with its ID, name, value and the meaning of its code. It also checks control numbers, counts and empty mandatory elements. All of that is free. Zovo Pro (USD 19 once) adds export to JSON or CSV, a compare of two files and a check of a whole folder, with 3 free tries each.

Free, MIT license. Extension ID zovo.zovo-edi-viewer, version 0.1.1. Needs VS Code 1.90.0 or newer.

Steps in VS Code

1. Install EDI Viewer from the Marketplace, or press Ctrl+P (Cmd+P on macOS) and run ext install zovo.zovo-edi-viewer.
2. Click the .edi, .x12, .edifact or .850-style file. It opens as EDI text with colors. Files that start with ISA, UNA or UNB are found by their first line, whatever their name.
3. Click the Open in EDI Viewer button in the editor title bar, or right-click the file in the Explorer and pick Open in EDI Viewer.
4. In the Tree tab, click a segment. The panel on the right lists each element with its ID (such as BEG03), name, value and code meaning. Double-click a row to select that segment in the text.
5. Open the Problems tab to see wrong control numbers, wrong counts, ISA fields with the wrong width and empty mandatory elements, each with its line.
6. Back in the text editor, rest the mouse on a value to see its name. Right-click and pick Format EDI (one segment per line) to read it line by line, or Minify EDI to put it back on one line.

Where Zovo Pro saves time

The tree, the Segments table with its filter, the Problems tab, names on hover, the Problems panel, Format EDI and Minify EDI are free, with no limit and no sign-in. The viewer is read-only and makes no network calls.

When a partner sends a batch of files, Validate a folder of EDI files checks every X12 and EDIFACT file in a folder. You get one report with errors, warnings, counts and the trading partners of each file (ISA06 and ISA08, or the UNB sender and recipient), as Markdown and CSV. The other two Pro tools export a file to JSON or CSV, and compare two files segment by segment.

With Validate a folder of EDI files (Zovo Pro)

7. Click Validate folder… at the top of the viewer, or run "EDI Viewer: Validate a folder of EDI files (Pro)" from the Command Palette.
8. Pick the folder. Every X12 and EDIFACT file in it is read and checked.
9. Read the Markdown report, or open the CSV in a spreadsheet. Cancel uses no free try.

Validate a folder of EDI files works 3 times on your computer before it asks for a license, and a try counts only when you get a result. Opening a file shows no popup and no countdown.

Zovo Pro costs USD 19 once. It is not a subscription, and it turns on the Pro tools in every Zovo extension, not only EDI Viewer. After a card payment (Stripe) your license key shows on the next page. In VS Code, run "Zovo Pro: Enter Zovo Pro license key" from the Command Palette and paste it. The key is checked on your computer, with no network call. With GitHub Sponsors, pick the "$19 one time" tier, then run "Zovo Pro: I already paid: unlock with GitHub Sponsors" and sign in with the same GitHub account. With PayPal, send USD 19 with "Zovo Pro" in the note and the key comes by email within a day.

A team of 5: USD 59 once, by card or by PayPal. Every rule and every Pro tool is on the Zovo Pro page.

Steps in Cursor, Windsurf or VSCodium

1. Open the Extensions view with Ctrl+Shift+X (Cmd+Shift+X on macOS).
2. Search for zovo.zovo-edi-viewer and click Install. Cursor, Windsurf and VSCodium install from Open VSX, where it is published as zovo/zovo-edi-viewer.
3. If your editor has no gallery, download the .vsix from the Open VSX page and run "Extensions: Install from VSIX...".
4. Then use it the same way as in VS Code.

What EDI Viewer handles

• X12 850, 855, 810, 856, 997, 999, 820, 837P, 837I, 835, 270, 271, 276, 277, 204, 214, 940 and 945, with names and common code lists.
• EDIFACT ORDERS, ORDRSP, DESADV, INVOIC, IFTMIN, PRICAT, APERAK and CONTRL, with names from the UN/CEFACT directories.
• Separators read from the ISA header or UNA, with or without line breaks.
• HL hierarchies and loops such as NM1, N1, PO1, LIN and CLM.

What it does not do

• It is a viewer. It does not translate EDI into your ERP, send files to partners or write 997 acknowledgments.
• Files up to 64 MB open, and up to 500,000 segments are shown.
• Names are short descriptions written for the extension, not the full X12 implementation guides.
• Transaction sets outside the lists above still open as segments, with fewer names.

Other options

• A plain text editor. Free. Replace the segment terminator with a line break to read one segment per line, with no names or checks.
• pyx12. A free Python library that parses and validates X12 files from a script.
• Online EDI viewers. Free websites that show a file as a tree. The file is uploaded to someone else's server.

Install counts and Open VSX status were checked on 12 November 2026. Descriptions in quotes are the extensions' own.

Questions

More about EDI Viewer

Read the EDI Viewer page for every feature and setting, or the source code on GitHub.

Related guides

• Format XML in VS Code and run XPath on it
• Validate a folder of X12 or EDIFACT files in VS Code
• Convert an EDI file to JSON or CSV
• Read a HAR file offline in VS Code