> For the complete documentation index, see [llms.txt](https://docs.intrepidcs.com/vspy-3-documentation/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.intrepidcs.com/vspy-3-documentation/3.9.15/vehicle-spy-main-menus/main-menu-spy-networks/message-editor/messages-editor-message-fields/message-length.md).

# Message Length

The **DLC** (Data Length Code) allows specification of the expected length for a CAN message (Figure 1).

Likewise, the Len column specifies the length for a LIN message.

![Figure 1: Specify Message Length in the DLC Column](/files/R3MNJzQvVSihM1JPkxBT)

When a message is received, its length is compared to the expected message length. If it doesn't match, the global error and expected length bits will be set in the message status field. Vehicle Spy will indicate an error by showing a red dot next to the message in [Messages](/vspy-3-documentation/3.9.15/vehicle-spy-main-menus/main-menu-spy-networks/messages-view.md) view.

Leave the length column blank to disable length checking.


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