How to open a JSON file online
Three steps, a few seconds, no software.
Open your .LDT file
Drop it on the box, choose it from your device, or paste the data straight in.
View the structure
Your .LDT 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 .LDT file?
The most common data format on the web.
An LDT file is a EULUMDAT photometric data file, plain text that describes how one light fixture distributes its light in every direction. Open it in DIALux, Relux, or IESviewer to run lighting calculations or view its light distribution. The only real conversion is LDT to IES (the North American equivalent format), done with IESviewer or an online converter.
Programs that open .LDT files
| Full name | EULUMDAT Photometric Data File |
|---|---|
| Developer | Axel Stockmar (Light Consult Inc., Berlin) — de-facto European industry standard, 1990 |
| First released | 1990 (EULUMDAT, proposed by Axel Stockmar as a European luminaire data exchange format) |
| Category | Text & Code |
| MIME type | text/plain |
Related viewers
Every viewer is free to use.
Frequently asked questions
Is my .LDT file uploaded anywhere?
No. The file is opened directly from the copy you pick.
My .LDT 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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