DisplayName
In OPC UA, DisplayName is a node's human-readable label, held as a LocalizedText with a locale identifier and text. Clients show it in browse trees and faceplates. It is localisable, may be changed by the server or an engineer, and must never be used as a programmatic identifier.
LocalizedText and locale negotiation
A DisplayName is a LocalizedText: a locale string such as en-US or de-DE plus the text itself. A client declares its preferred locales in the LocaleIds list on CreateSession or ActivateSession, and the server returns the best match it holds. Servers that carry only one translation return that one regardless, with a locale of null or an empty string, which is legal.
Where the value comes from
For standard nodes the DisplayName usually equals the BrowseName text, which is why the distinction looks academic on a reference server and bites in the field. PLC and gateway servers frequently derive DisplayName from an engineering comment or a tag description, so it can contain spaces, units, plant-specific abbreviations and mixed case. Some servers expose DisplayName as writable so operators can relabel a faceplate.
Related human-facing attributes
Description is the optional longer LocalizedText on the same node, and it is the field most servers leave empty. Together with the DisplayName it is what an HMI or a dashboard should render. Nothing in Part 3 requires DisplayName to be unique among siblings, so two children of the same folder can both display as Temperature while having different BrowseNames.
Defined in: Part 3 - Address Space Model, DisplayName and Description attributes; LocalizedText is defined in Part 3 and encoded per Part 6.
Last verified 7 September 2026 against OPC UA 1.05.07. OPC UA Connect is an educational resource and is not affiliated with the OPC Foundation.