Adobe InDesign has default support for the export to JPG format. You can select any element in .indd document and with the File ► Export function save it as a .jpg image. Plenty of settings and other options exists, so you can tweak the output image settings before you save it.
Some alternative "indd to jpg conversion" would be just scanned pages of the InDesign document. You can do that with various screen capturing tools, but that actually far from actual export or conversion.
As far as we know, there are no website tools available that can convert indd to jpg online.Open INDD file Open JPG file
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