How to open a JSON file online
Three steps, a few seconds, no software.
Open your .XTM file
Drop it on the box, choose it from your device, or paste the data straight in.
View the structure
Your .XTM file opens as a tidy, foldable tree, with the exact line of any error pointed out.
Search, copy or download
Search keys and values, copy any path or value, switch to a table, or download a clean copy.
What is a .XTM file?
The most common data format on the web.
An XTM file is an XML Topic Map, a structured knowledge model that stores topics, their names, typed relationships, and links to information resources, following the ISO 13250 standard. CmapTools (free) is the main application for opening and editing XTM files; any text or XML editor opens the raw markup. The format is plain XML with no executable code, so it is safe to open.
Programs that open .XTM files
| Full name | XML Topic Map |
|---|---|
| Developer | TopicMaps.Org Authoring Group (XTM spec); IHMC (CmapTools implementation) |
| First released | August 2001 (XTM 1.0 published by TopicMaps.Org) |
| Category | Text & Code |
| MIME type | application/x-tm+xml |
Related viewers
Every viewer is free to use.
Frequently asked questions
Is my .XTM file uploaded anywhere?
No. The file is opened directly from the copy you pick.
My .XTM file is invalid. Can you fix it?
We show the exact line and column of the first error. For common problems like comments, trailing commas, single quotes or Python-style True/False/None, click Try to repair and download the fixed file.
How large can the file be?
Up to 50 MB. The tree only builds the branches you open, so even multi-megabyte files stay responsive.
What is JSONPath?
A path like $.orders[3].customer.email that points to one value inside the data. Click any node to see its path and copy it for code, jq or your API docs.
Can I see my data as a table?
Yes. Any array of objects can be shown in the Table view and downloaded as CSV.
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