Tools

LTE, NB-IoT and LTE-M bands — EARFCN explorer

Convert between band, frequency (uplink and downlink) and EARFCN channel number, with the NB-IoT and LTE-M bands flagged. Enter an EARFCN and we tell you its band and frequency; pick a band and we give you its full range. Arithmetic and table per 3GPP TS 36.101. Everything is computed in your browser.

Look up an EARFCN

Enter the channel number (EARFCN) your modem reports.

EARFCN

Explore a band

Band

Duplex mode: FDD
Downlink (DL): 791.0 – 820.9 MHz
Uplink (UL): 832.0 – 861.9 MHz
Band width: 29.9 MHz
EARFCN (DL): 6150 – 6449
EARFCN (UL): 24150 – 24449
IoT: NB-IoTLTE-M

Band table

Band	Spectrum	Downlink (MHz)	EARFCN (DL)	Duplex	IoT
B1	2100 MHz	2110.0–2169.9	0–599	FDD	NB-IoTLTE-M
B2	1900 MHz PCS	1930.0–1989.9	600–1199	FDD	NB-IoTLTE-M
B3	1800 MHz	1805.0–1879.9	1200–1949	FDD	NB-IoTLTE-M
B4	AWS-1	2110.0–2154.9	1950–2399	FDD	NB-IoTLTE-M
B5	850 MHz	869.0–893.9	2400–2649	FDD	NB-IoTLTE-M
B7	2600 MHz	2620.0–2689.9	2750–3449	FDD	LTE-M
B8	900 MHz	925.0–959.9	3450–3799	FDD	NB-IoTLTE-M
B12	700 MHz a	729.0–745.9	5010–5179	FDD	NB-IoTLTE-M
B13	700 MHz c	746.0–755.9	5180–5279	FDD	NB-IoTLTE-M
B14	700 MHz PS	758.0–767.9	5280–5379	FDD	LTE-M
B17	700 MHz b	734.0–745.9	5730–5849	FDD	NB-IoT
B18	800 MHz Japan	860.0–874.9	5850–5999	FDD	NB-IoTLTE-M
B19	800 MHz Japan	875.0–889.9	6000–6149	FDD	NB-IoTLTE-M
B20	800 MHz EU DD	791.0–820.9	6150–6449	FDD	NB-IoTLTE-M
B25	1900 MHz ext PCS	1930.0–1994.9	8040–8689	FDD	NB-IoTLTE-M
B26	850 MHz ext	859.0–893.9	8690–9039	FDD	NB-IoTLTE-M
B28	700 MHz APT	758.0–802.9	9210–9659	FDD	NB-IoTLTE-M
B66	AWS-3	2110.0–2199.9	66436–67335	FDD	NB-IoTLTE-M
B71	600 MHz	617.0–651.9	68586–68935	FDD	NB-IoTLTE-M
B85	700 MHz ext	728.0–732.9	70546–70595	FDD	NB-IoTLTE-M
B34	2000 MHz TDD	2010.0–2024.9	36200–36349	TDD	—
B38	2600 MHz TDD	2570.0–2619.9	37750–38249	TDD	LTE-M
B39	1900 MHz TDD	1880.0–1919.9	38250–38649	TDD	LTE-M
B40	2300 MHz TDD	2300.0–2399.9	38650–39649	TDD	LTE-M
B41	2500 MHz TDD	2496.0–2689.9	39650–41589	TDD	NB-IoTLTE-M

The NB-IoT / LTE-M flag means the 3GPP standard defines those categories on the band; real support depends on the module and the operator.

How band, frequency and EARFCN relate

Every LTE channel is identified by an integer, the EARFCN, which 3GPP TS 36.101 turns into a frequency with a simple formula: the downlink frequency is the band's base frequency plus 0.1 MHz for each EARFCN step above that band's offset. The downlink and uplink numbers occupy separate ranges, so an EARFCN unambiguously tells you whether it is a downlink or uplink channel — except on TDD bands, where uplink and downlink share the same frequency and numbering. Knowing the band matters in IoT because it drives coverage and indoor penetration: low bands like 20 (800 MHz) or 8 (900 MHz) reach farther and go through walls better, which is why they're preferred for NB-IoT and LTE-M in Europe, while high bands give more capacity but less range. Checking which band and frequency a module is operating on is one of the first steps when diagnosing coverage or certifying a device for a specific network.

Frequently asked questions

What is an EARFCN?

EARFCN (E-UTRA Absolute Radio Frequency Channel Number) is the integer that identifies a radio channel in LTE. 3GPP TS 36.101 assigns each band a range of EARFCNs and a formula to go from number to frequency: downlink frequency = band base frequency + 0.1 MHz × (EARFCN − offset). Each operator publishes the EARFCNs it uses; the modem reports the current one with vendor commands.

Which bands are used for NB-IoT and LTE-M?

NB-IoT and LTE-M are defined by 3GPP over a subset of the LTE bands. In Europe the most common are band 20 (800 MHz) and band 8 (900 MHz) for their range and indoor penetration; in North America bands 12, 13 and 71 (700–600 MHz) and 2/4/66 are widely used. This tool's table flags each band with the profiles the standard defines; real support depends on the module and the operator.

Why do uplink and downlink have different frequencies?

On FDD bands (most in Europe) uplink and downlink use separate frequencies so the device can transmit and receive at the same time; that's why each band has an uplink frequency range and a downlink one, with distinct EARFCN ranges. On TDD bands uplink and downlink share the same frequency and alternate in time, so a single EARFCN serves both directions.

How do I know which band my device is on?

Most modules report the active band or EARFCN through vendor AT commands (for example AT+QCAINFO, AT#RFSTS or your modem's equivalent). Given the EARFCN, this tool gives you the exact band and frequency; combined with the signal interpreter, you can see whether that band is giving you good coverage.