What is the undeciphered script of the Indus Valley Civilization called?

The undeciphered script of the Indus Valley Civilization is called the Indus script.

It is also known as the Harappan script or Indus Valley script. The symbols appear on stamp seals, pottery, copper and bronze objects, tools, and other artifacts produced by the Bronze Age Indus or Harappan Civilization. Most inscriptions are extremely short, often consisting of only a few signs, which makes their meaning difficult to reconstruct.

Scholars generally agree that many inscriptions were written from right to left, although exceptions exist. More than 400 principal signs have been identified, but researchers still disagree about whether the symbols represent a complete writing system, a form of proto-writing, or a system of administrative marks.

The script remains undeciphered because no bilingual inscription equivalent to the Rosetta Stone has been found, and the underlying Harappan language is unknown. Proposed links with Dravidian, Indo-Aryan, and other language families remain unproven. Devanagari, Brahmi, and Kharosthi are different scripts from later periods and should not be confused with it.