Decode and encode 5G NR Cell Identity (NCI). Extract gNB-ID and Cell Local ID from any NCI value, or build NCI from gNB-ID components.
NCI is a 36-bit identifier. With the default 22-bit gNB-ID, there are up to 4,194,303 unique gNBs, each supporting up to 16,384 cells (14-bit Cell Local ID).
NCI → gNB-ID + Cell Local ID
gNB-ID (decimal)
gNB-ID (hex)
Cell Local ID (decimal)
Cell Local ID (hex)
NCI (hex, 9 digits)
NCI (binary, 36 bits)
gNB-ID bits
Cell Local ID bits
gNB-ID + Cell Local ID → NCI
NCI (decimal)
NCI (hex, 9 digits)
NCI (binary, 36 bits)
gNB-ID (hex)
Cell Local ID (hex)
gNB-ID bits
Cell Local ID bits
Frequently Asked Questions
What is 5G NR Cell Identity (NCI)?
NCI (NR Cell Identity) is a 36-bit identifier used in 5G NR to uniquely identify a cell within a gNB (gNodeB). It is composed of two parts: the gNB-ID (identifying the base station) and the Cell Local ID (identifying the cell within that base station). NCI is defined in 3GPP TS 38.413 and is used in the NG-RAN architecture.
What is gNB-ID?
gNB-ID is the portion of the NCI that identifies the 5G base station (gNodeB). Its bit length is configurable by the network operator — typically 22, 24, 28, or 32 bits. With a 22-bit gNB-ID, up to 4,194,303 unique gNBs can be addressed. The remaining bits (36 minus gNB-ID bits) form the Cell Local ID, identifying up to 16,384 cells per gNB with the default 22-bit configuration.
How is NCI different from Physical Cell ID (PCI)?
NCI (NR Cell Identity) is a logical 36-bit global identifier assigned by the network operator and used for core network signaling and cell management. PCI (Physical Cell ID) is a physical layer identifier ranging from 0 to 1007, used by UEs for radio-level identification during cell search and handover. Multiple cells can share the same PCI across different geographic areas, but NCIs are unique within a PLMN.