EDI viewers compared: free online tools and desktop apps

The tools below are the ones that actually turn up when EDI people look for a viewer, plus the two text editors that get pressed into service. Prices and capabilities were checked in September 2026 against each vendor's own page; they change, so confirm before you buy. EDI Studio is our product and it is on the list — the honest summary is that it is the right choice in a specific situation and not in others, and the table says which.

The short version

• You need to glance at a file once, right now: a free browser viewer. EdiPeek if you care that the file never uploads; Stedi's Inspector if you also want inline validation and do not mind an account.
• You read EDIFACT as well as X12: the browser tools and EDIdEv's eFileManager handle both. EDI Studio does not read EDIFACT.
• You work in files every week, on a Mac, or on documents you are not allowed to upload: a desktop application. On Windows that is eFileManager or X12 Studio; on macOS, EDI Studio is currently the only native option we know of.
• You edit as often as you read: pick a tool that repairs the envelope counts after an edit (SE01, GE01 and the control numbers). Text editors will not, and most viewers will not either.

Comparison at a glance

Checked September 2026. “File stays local” means the document is parsed on your own machine rather than sent to the vendor's server; for browser tools that claim client-side parsing, the claim is the vendor's.

Stedi EDI Inspector

Stedi is an EDI platform and clearinghouse, and the Inspector is its free reader: paste X12 or EDIFACT and it renders the document in a readable form with inline validation errors, and with an account you can edit and debug the file. It is the most polished of the browser tools and the natural pick if you are already a Stedi customer. It is a tab, not a file tool — there is no folder of last week's interchanges, no multi-document workspace, and saving a corrected file back to disk is not the workflow it is built for.

EdiPeek

A free, donation-supported viewer that parses X12 and EDIFACT in the browser and states plainly that the file never leaves your computer. It adds a plain-English summary of what the transaction means and some envelope and count checks. No editing, no account. For a quick look at a file you are allowed to open in a browser, it is hard to argue with.

EdiNation (EdiFabric)

EdiFabric sells developer libraries for .NET; EdiNation is its free online translator, validator and editor for X12 and EDIFACT. It uploads the file to translate it, which rules it out for documents under an NDA or a HIPAA agreement, but the validation is thorough and it is a reasonable way to see what a developer-grade parser makes of a file.

EDIFACTORY EDI Viewer

A German directory of EDI standards with a viewer attached: upload a message and it is shown segment by segment with the code and qualifier explanations from EDIFACTORY's guideline database. Strongest on EDIFACT and on guideline-driven validation. Basic use is free; professional accounts are quoted on request.

EDIdEv eFileManager

The established Windows desktop answer. eFileManager is bundled in EDIdEv's Desktop Utility with eAnalyzer, which validates X12 and EDIFACT files against SEF implementation guidelines — the most rigorous validation on this list if your trading partner publishes a SEF file. It is a single-user perpetual licence at $450, Windows only, and the interface shows its age, but for a Windows analyst who needs guideline-level validation it remains a serious tool.

X12 Studio Toolbox

Caliber Health's Windows toolbox, with a free tier that opens, parses and edits X12 and paid components on top. It comes from the healthcare side of X12 (837 claims, 835 remittances) and is a good fit there; supply-chain sets are supported as X12 but that is not where its dictionaries are deepest.

Liaison EDI Notepad

For years the default Windows viewer, in a free Express edition and a paid Professional one. It is no longer sold or maintained following Liaison's acquisition by OpenText. If you have a copy it still opens files; if you are looking for it, you are looking for a replacement, and the dedicated comparison covers that.

Notepad++ and UltraEdit

Both open an X12 file as text, and with a user-defined language or column mode you can make the segments easier to scan. Neither parses the file: nothing names the elements, nothing validates, and an edit that changes the segment count leaves SE01 wrong until you fix it by hand. They are what most people use before they buy a viewer, which is exactly why the viewers exist.

EDI Studio

Our product, so read this paragraph with that in mind. EDI Studio is a native desktop application for macOS and Windows that parses X12 into a tree, groups validation errors by the root cause that produced them, and lets you edit a segment in place with the envelope counts repaired on save. Files are never uploaded. It is the right tool if you work in X12 files regularly, need a Mac build, or handle documents you cannot put in a browser. It is the wrong tool if you need EDIFACT, guideline-level SEF validation, translation or mapping — it does none of those. The 7-day trial is the full application and needs no card.