GSM Cell ID explained

A GSM Cell ID (CID) is a generally unique number used to identify each base transceiver station (BTS) or sector of a BTS within a location area code (LAC) if not within a GSM network.

In some cases the first or last digit of CID represents cells' Sector ID:

• value 0 is used for omnidirectional antenna,
• values 1, 2, 3 are used to identify sectors of trisector or bisector antennas.

In UMTS, there is a distinction between Cell ID (CID) and UTRAN Cell ID (also called LCID). The UTRAN Cell ID (LCID) is a concatenation of the RNC-ID (12 bits, ID of the Radio Network Controller) and Cell ID (16 bits, unique ID of the Cell). CID is just the Cell ID. The concatenation of both will still be unique but can be confusing in some cellid databases as some store the CID and other store LCID. It makes sense to record them separately as the RNC ID is the same for many cells, the unique element is the CID.

A valid CID ranges from 0 to 65535 (2¹⁶ − 1) on GSM and CDMA networks and from 0 to 268,435,455 (2²⁸ − 1) on UMTS and LTE networks.^[1]

Cell ID databases and services

A number of commercial and public Cell ID databases and services are available:

Name	Unique cells	Countries (MCC)	Operators (MNC)	Measurements	Free database download	Active project	Data license	Comment
Cell Spotting	0.1 million^[2]		667			no
Combain Mobile	>140 million^[3]	>240	>1700	>131 billion	no	yes		Supports GSM, CDMA, UMTS, LTE and NR via API.^[4]
LocationAPI.org	157.89 million^[5]	240	1712	25 billion	no	yes		Supports WiFi, GSM, CDMA, UMTS and LTE technologies via its API. ^[6]
Mozilla Location Service	28.2 million^[7]	240^[8]		2.7 billion	yes^[9]	no^[10]		Based on crowd-sourced data. Also WiFi database. Cooperating with OpenCelliD and Combain.^[11]
Mylnikov GEO^[12]	>34 million	505	3500		yes	no^[13]		Contains data from radiocells.org, OpenCellID and MLS.
Navizon^[14]	71 million	239	1712	22 billion	no	yes		Based on crowd-sourced data. Also WiFi database.^[15]
NetMeterProject.com	0.2 million	77	174	10 million	limited; private use only	no ^[16]		Only a small portion of the database can be downloaded and for private use only: the measurements where the crowd users accepted the "Creative Commons Namensnennung-Nicht-kommerziell-Weitergabe unter gleichen Bedingungen 3.0 Deutschland" license
OpenCellID by Unwired Labs^[17]	38.9 million	222	753	2.1 billion	yes	yes		Based on crowd-sourced data; free API key required for database download; Service is now maintained by Unwired Labs.^[18]
OpenSignal^[19]	0.8 million		825	5.2 billion	no	yes
radiocells.org^[20]	0.7 million	94	243		yes	yes		Based on crowd-sourced data.
WiGLE^[21]	6.2 million				no	yes
CellMapper					no	yes
OpenMobileNetwork
G-NetWold by Gyokov Solutions
Skyhook Wireless
Google Location Services^[22]
Apple Location Services^[23]
Microsoft Location Services^[24]

See also

• Base transceiver station
• Field test mode
• E-CellID

External links

• Combain Positioning Service - cloud service with API to locate wireless devices based on Cell-ID and Wi-Fi
• LocationAPI by Unwired Labs - Location as an API service to locate devices with WiFi, Cell towers & IP
• Mozilla Location Service - an open service which lets devices determine their location based on network infrastructure like WiFi access points and cell towers
• CellMapper - cellular coverage and tower map
• OpenCellID - an open source project, aiming to create a complete database of Cell IDs worldwide, with their locations
• cellidfinder - Find the coordinates of any known CellID.
• Navizon - cloud service with API to locate wireless devices using a global database of WiFi access points and Cell-ID locations
• openBmap - a free and open map of wireless communicating objects (e.g. cellular antenna, Wi-Fi access points...)
• minigps - some information on Cell IDs in china
• Mylnikov GEO - an open source API project. It lets get coordinates of mobile towers with no limits and absolutely free. (Russian)
• Base Station Numbering Schemes - Discussion of cellular repeater numerology

Notes and References

1. Web site: Cell Networks. 21 September 2015. https://web.archive.org/web/20160304211934/https://mozilla.github.io/ichnaea/internal_api/models/cell.html#cell-networks. 4 March 2016. dead. dmy-all.
2. Web site: CellSpotting Stats . 2016-03-29 . https://web.archive.org/web/20080101015633/http://www.cellspotting.com/thick/statistics.php . 2008-01-01 . dead .
3. Web site: Combain Mobile . 2023-02-23 .
4. Web site: Combain Location API . 2023-02-23 .
5. Web site: Unwired Labs LocationAPI . 2016-03-29 .
6. Web site: Unwired Labs Coverage Map . 2016-03-29 .
7. Web site: Statistics - Mozilla Location Service . 2016-03-29 .
8. Web site: Per Country Cell Statistics - Mozilla Location Service . 2016-03-29 .
9. Web site: Cell Download - Mozilla Location Service . 2020-12-17 .
10. Web site: Retiring the Mozilla Location Service . 2024-07-26 .
11. Web site: Combain Deal Helps Expand Mozilla Location Service . 2015-04-09 .
12. Web site: Stats Mylnikov GEO Cells. 2016-03-29 .
13. Web site: Mylnikov Download page . 2020-12-17 .
14. Web site: Navizon Global Positioning System . 2016-03-29 . 2021-01-19 . https://web.archive.org/web/20210119081128/http://navizon.com/wifi-cell-tower-location-database . dead .
15. Web site: Navizon Cellular Coverage Map . 2016-03-29 . 2017-11-23 . https://web.archive.org/web/20171123154840/http://navizon.com/navizon_coverage_cell.htm . dead .
16. Web site: Board NetMeterProject . 2016-03-29 .
17. Web site: opencellid.org Realtime Statistics . 2015-08-30 .
18. Web site: OpenCellID wiki. 2017-03-02.
19. Web site: Stats OpenSignalMap. 2014-09-06. https://archive.today/20150502112843/http://opensignal.com/coverage-maps/#. 2015-05-02. dead.
20. Web site: radiocells.org . 2016-03-29 .
21. Web site: Stats WiGLE. 2016-03-29 .
22. Web site: Google Location Service in Mozilla Firefox Privacy Policy. Google Inc.. 2016-09-30.
23. Web site: About Location Services and Privacy. Apple Inc.. 2016-09-30.
24. Web site: Windows Runtime APIs - Windows.Devices.Geolocation namespace. Microsoft Corp.. 2016-09-30.